bi- 1或 bin-
pref.（前缀）

Two:
二：
biform.
二形的
Both:
两者都的：
binaural.
两耳的
Both sides, parts, or directions:
双边、双方或双向的：
biconcave.
双凹的

Occurring at intervals of two:
每二的（发生一次）：
bicentennial.
每二百年的
Usage Problem Occurring twice during:
【用法疑难】每…二次的：
biweekly.
每周二次的

Containing twice the proportion of a specified chemical element or group necessary for stability:
为达到稳定而需要含有两个化学元素或两个基团的：
bicarbonate.
碳炭氢盐
Containing two chemical atoms, radicals, or groups:
含有两个原子、根或基团的：
biphenyl.
联二苯

语源

Latin bis, bi- [twice,]
拉丁语 bis, bi- [两次，]
bīnī [two by two] * see dwo-
bīnī [两个两个的] *参见 dwo-

用法

Bimonthly and biweekly mean “once every two months” and “once every two weeks. ” For “twice a month” and “twice a week,”the wordssemimonthly and semiweekly should be used. Since there is a great deal of confusion over the distinction,a writer is well advised to substitute expressions likeevery two months or twice a month where possible. However, used as nouns to denote “a publication that appears every two months,”the words withbi- are unavoidable.
Bimonthly 和 biweekly 意为“每两个月一次”和“每两个星期一次。” 如表示“一个月两次”或“一个星期两次”，应该用semimonthly 和 semiweekly。因在区别上存在很大混乱，建议作者尽可能用every two month 或 twice a month 的表达法代替。但当用作名词表示“每两个月出版一次的刊物（双月刊）”时，不可避免地要使用含有bi- 的词

bi- 2
pref.（前缀）

Variant of bio-
bio-的变体

bi-¹ or (sometimes before a vowel) bin-

combining form

two; having two

⇒ bifocal

occurring every two; lasting for two

⇒ biennial

on both sides, surfaces, directions, etc

⇒ bilateral

occurring twice during

⇒ biweekly

denoting an organic compound containing two identical cyclic hydrocarbon systems

⇒ biphenyl

(rare in technical usage) indicating an acid salt of a dibasic acid

⇒ sodium bicarbonate

(not in technical usage) equivalent of di-¹ (sense 2a)

Origin

from Latin, from bis twice

bi-²

combining form

a variant of bio-

bio- or (before a vowel) bi-

combining form

indicating or involving life or living organisms

⇒ biogenesis

⇒ biolysis

indicating a human life or career

⇒ biography

⇒ biopic

Origin

from Greek bios life

bi-¹

Word Origin

1

a combining form meaning “twice,” “two,” used in the formation of compound words:

bifacial; bifarious.

Compare bin-.

Origin

< Latin, combining form of bis; see twice

Usage note

All words except biennial referring to periods of time and prefixed by bi-¹ are potentially ambiguous. Since bi- can be taken to mean either “twice each” or “every two,” a word like biweekly can be understood as “twice each week” or “every two weeks.” To avoid confusion, it is better to use the prefix semi- to mean “twice each” (semiannual; semimonthly; semiweekly) or the phrase twice a or twice each (twice a month; twice a week; twice each year), and for the other sense to use the phrase every two (every two months; every two weeks; every two years).

bi-²

1

variant of bio-, especially before a vowel:

biopsy.

bi-a prefix meaning 'twice, doubly, two', as in bilateral, biweekly.

Also, bin-. [Latin, combining form of bis twice, doubly]

bi-

I

prefix

ETYMOLOGY Middle English, from Latin — more at twi-

1.
  a. two
      bilateral
  b. coming or occurring every two
      bicentennial
  c. into two parts
      bisect
2.
  a. twice : doubly : on both sides
      biconvex
  b. coming or occurring two times
      biannual
  — compare semi-
3. between, involving, or affecting two (specified) symmetrical parts
    bilabial
4.
  a. containing one (specified) constituent in double the proportion of the other constituent or in double the ordinary proportion
      bicarbonate
  b. di- 2
      biphenyl
Usage.
  Many people are puzzled about bimonthly and biweekly, which are often ambiguous because they are formed from both senses 1b and 2b of bi-. This ambiguity has been in existence for nearly a century and a half and cannot be eliminated by the dictionary. The chief difficulty is that many users of these words assume that others know exactly what they mean, and they do not bother to make their context clear. So if you need bimonthly or biweekly, you should leave some clues in your context to the sense of bi- you mean. And if you need the meaning “twice a,” you can substitute semi- for bi-. Biannual and biennial are usually differentiated.

II

combining form
or bio-

ETYMOLOGY Greek, from bios mode of life — more at quick

1. life : living organisms or tissue
    bioluminescence
    biosphere
2. biographical
    biopic

bi-

/baɪ/

combining form

two; having two 表示“二”, “具有两个”：: bicoloured

biathlon.

参见BIN-.

■ occurring twice in every one or once in every two 表示“每…两次”, “每两…一次”：: bicentennial.

■ lasting for two 表示“持续两…的”：: biennial.

■ doubly; in two ways 表示“两倍”, “两方面地”：: biconcave.

■ Chemistry (in names of compounds) containing two atoms or groups of a specified kind 【化】［用于化合物名称］表示“联（二）”：: bicarbonate.

■ Botany & Zoology (of division and subdivision) twice over 【植, 动】表示“（部或亚门）二回”：: bipinnate.

USAGEThe meaning of bimonthly （and other similar words such as biweekly and biyearly） is ambiguous. Such words can either mean 'occurring or produced twice a month' or 'occurring or produced every two months'. The only way to avoid this ambiguity is to use alternative expressions like every two months and twice a month. Biannual and biennial are also confusing： biannual means 'occurring twice a year' and biennial means 'occurring every two years'.

词源

from Latin, 'doubly, having two'; related to Greek di- 'two'.

▪ I.bi- prefix¹the early OE., and the ordinary ME., form of the prefix be-; under which spelling see most of the words. Those alone are left under bi-, which did not survive long enough to be spelt with be-.▪ II.bi- prefix²a. L. bi- (earlier dui-, cogn. with Gr. δι-, Skr. dvi-) ‘twice, doubly, having two, two-,’ which is in Latin a prefix of adjs., occas. of ns., rarely of vbs. (e.g. bipertīre). The earliest Latin adjs. of this type are formed by simply prefixing bi- either to adj.- (and verb-) stems, as bifer, bifidus, bijugus, bisonus, or to n.- (and adj.-) stems, as bicolor, biceps, bifrons, bifurcus, bigener; later in all probability, and more evidently mere compounds, are those in which bi- is prefixed to an adj. with a thematic suffix, as bicorniger, bicubitālis, bilongus, bipatens, and these are occas. participial in form, as bicamerātus, biformātus. The Latin ns., ending usually in -ium, are formed on the prec. adjs., or possible ones of corresponding type, as biennium a space of two years, biennis lasting two years, biclīnium, *biclīnus.The prefix entered Eng. in composition, e.g. in bigam (= med.L. bigamus), found c 1300, bicorne, c 1420; bifront, biforked occur late in 16th c.; and from the 17th c. onward, by a wide extension of the Latin analogy, especially in its later phases, bi- has been prefixed to any adj. conveniently indicating the thing or quality which is to be described as doubled or occurring twice, principally to those of Latin etymology, as in biangular, bicavitary, bicentral, bivaulted, bivoluminous, but also to others as birainy, biweekly. In modern scientific terminology, adjs. in -ate, -ated are most frequently employed, as biauriculate, bicarinate, bilamellate, bipinnate, biunguiculate, bimaculated; and the attrib. use of ns. as adjs. tends to such modern forms as bichord, biwhirl. (See also the form bin-.)Bi- is therefore used in Eng. to form:—I. Adjectives, with the sense:—1. Having or furnished with two —, two-—, as bi-angular, -ate, -ated, -ous, having two angles; bibracteate, having two bracts; bibracteolate, having two small bracts; bicallose, -ous, having two callosities; † bicapited, bicapitate, having two heads, two-headed; bicapsular; bicavitary, having two cavities; bicentral; bichord, having two strings; biciliate, having two cilia or hairs; bicoloured, bicolumnar, biconsonantal; bicorporal, -ate, -ated, -eal, having two bodies; bicristate, having two crests; bifanged; biglandular, having two glands; bimarginate, bimembral, bimuscular; binodal, having two nodes; binuclear, having two nuclei; bi-ovulate, bipetalous; biporose, having or opening by two pores; bipupillate, having two pupil-like markings; biradiate, having two rays; birainy, having two rains or rainy seasons; bispinous, bistipuled; bitentaculate, having two tentacles; bituberculate, -ated, having two tubercles; bivascular, having two vessels; bivaulted; bivoluminous, consisting of two volumes; biwhirl.1870Hooker Stud. Flora 259 Peduncles *bi-bracteate at the forks.Ibid. 345 Scale peltate, *bi-bracteolate.1572J. Bossewell Armorie ii. 42 [Lions] are borne in armes..*Bicapited, Bicorporated, Tricorporated.1679Plot Staffordsh. (1686) 196 The *bicapsular seed vessel of Digitalis ferruginea.1870Rolleston Anim. Life Introd. 101 Nerve-centres..spoken of as ‘*bicavitary.’1854Maxwell in Life viii. 231 Full of ellipses—*bicentral sources of lasting joy.1857Berkeley Cryptog. Bot. §136 *Biciliate spores.1862R. Patterson Ess. Hist. & Art 34 A *bi-coloured uniform.1884M. Rule Eadmeri Hist. Nov. Pref. 84 The pages are *bicolumnar.1861Max Müller Sc. Lang. vii. 251 A *bi⁓consonantal root.1839Bailey Festus viii. (1848) 94 Luxurious, violent, *bicorporate.1686Goad Celest. Bodies ii. iv. 201 Airy Signs, or Signs *Bicorporeal.1882R. Brown Law Kosmic Ord. 57 A gigantic *bicorporeal Scorpion-couple.1852Dana Crust. i. 212 Fourth [joint] prominently *bicristate, the crests thin.1851Richardson Geol. viii. 315 Small *bifanged molar teeth.1876Harley Mat. Med. 441 Terminal panicles..supported by *biglandular bracts.1812J. Jebb Corr. (1834) II. 77 In these stanzas, each line is obviously *bimembral.1835Kirby Hab. & Inst. Anim. I. viii. 237 The first [order] is *Bimuscular, having two attaching muscles.1835Lindley Introd. Bot. (1848) I. 324 The cyme..may be *binodal, trinodal.1880Times 24 Nov. 10 A small *bi-nuclear, gaseous, planetary nebula.1881Gard. Chron. No. 411. 621 Spores..cylindrical, *binucleate.1858W. Clark Van der Hoeven's Zool. II. 145 Ventral fins *biradiate.1855Maury Phys. Geog. Sea v. §296 Bogota is within the *birainy latitudes.1852Dana Crust. i. 621 The preceding segment is *bispinous.1877Huxley Anat. Inv. An. iii. 131 A ciliated *bitentaculate body.1849Proc. Berw. Nat. Club II. vii. 371 A minutely *bituberculated wart.1809J. Barlow Columb. ix. 15 In this *bivaulted sphere.1870Lowell in Athenæum 19 Mar. 380 That *bivoluminous shape in which dullness overtakes..genius at last.1882in Nature XXVI. 546 The formation of whirl and *biwhirl systems.2. Doubly ―; ― in two ways or directions, on both sides; as bi-bisalternate (see quot.); bicleft; biconic, conical in two directions; biconcave, biconstant, biconvex; bicrescentic, crescent-shaped on both sides; bicurvate, bifusiform, bipyramidal, birectangular, birefracting, -ive, birefringent, birhomboidal, bi-sphero-concave; bisubstituted.1817R. Jameson Char. Min. 210 When there are two rows of bisalternate planes on each side, as in the *bibisalternate cinnabar.1627Drayton Agincourt, etc. 216 Those sacred springs, which from the *by-clift hill Dropt their pure Nectar.1854Woodward Mollusca (1856) 285 Shell inversely conical, *bi-conic, or cylindrical.1833Lyell Elem. Geol. xvii. (1874) 291 This Bird approaches the reptilian type in possessing *biconcave vertebræ.1836Todd Cycl. Anat. & Phys. I. 409/1 A *biconcave disc.1880Nature XXI. 289 A *bi-constant dispersion formula.1849–52Todd Cycl. Anat. & Phys. IV. 1438/2 When the rays pass out from a *bi-convex lens.1854J. Hogg Microsc. ii. ii. (1867) 400 Spicula having both extremities bent alike—*bicurvate.1831Brewster Optics xxix. 243 The *bipyramidal dodecahedron.1869Tyndall Notes Light 75 A *birefracting prism of Iceland spar.Ibid. 66 This crystal is *birefractive.1880Nature XXI. 204 A *birefringent crystal.1817R. Jameson Char. Min. 202 A crystal is said to be *bi-rhomboidal, when its surface consists of..two different rhomboids.1849–52Todd Cycl. Anat. & Phys. IV. 1469/1 *Bi-sphero-concave lenses.1880E. Cleminshaw Wurtz' Atom. Th. 303 In a *bisubstituted derivate of marsh gas, the third substitution may take place on either side.3. Bot. and Zool. Twice over, re- ―; i.e. having characteristically divided parts which are themselves similarly divided; as bilaciniate, bipinnate, biserrate, biternate, q.v.4. Lasting or continuing for two ―; occurring or appearing every two ―; as biennial, bi-hourly, bi-monthly, bi-weekly.1843in Proc. Amer. Philos. Soc. II. 247 *Bi-hourly observations..had ceased with the first of the present year.1879Gladstone in Daily News 1 Dec. 6/5 Annual as opposed to *bi-monthly or tri-monthly budgets.b. Occurring or appearing twice in a ―; as in bi-diurnal, bi-monthly, bi-quarterly, bi-weekly, bi-winter, bi-yearly. (The ambiguous usage is confusing, and might be avoided by the use of semi-; e.g. semi-monthly, semi-weekly; cf. half-yearly.)1854Woodward Mollusca (1856) 32 A *bi-diurnal visit from the tide.1878Print. Trades Jrnl. xxv. 4 A new Spanish *bi-monthly journal.1884Pall Mall G. 15 Feb. 16 To issue these etchings in *bi-quarterly numbers.1885Farrar Camb. Bible Sch. Luke xviii. 12 The *bi-weekly fast of the Pharisees..The days chosen were Thursday and Monday.1884Harper's Mag. Feb. 394/1 The mail-carriers are making one of their *bi-winter trips.1879Print. Trades Jrnl. xxviii. 9 A *bi-yearly calendar.c. The prec. adjs. in -ly are also used adverbially.1864Even. Standard 29 Oct., Sixpenny parts, to be issued bi-monthly.1865Reader 12 Aug. 188/3 To be held bi⁓weekly, on Mondays and Thursdays.d. The adjs. are also used substantively: bi-weekly, a newspaper, magazine, etc., published once every two weeks.1890in Webster.1978Daily Tel. 2 Dec. 1/7 The remainder are weeklies, bi-weeklies and three provincial Sunday newspapers.5. Joining or connecting two ―; as bi-acromial, bi-ischiatic, bi-parietal, q.v.6. Occasionally in other senses, as bimanual, employing two hands; biseriate, arranged in two series; bitaurine, belonging to two bulls.1872F. Thomas Dis. Women 73 The practice of *bimanual palpation.1882Vines Sachs' Bot. 430 The *biseriate segmentation of the apical cell.1864E. Swifte in N. & Q. V. 142 The *bitaurine bellow.II. Adverbs, verbs, and substantives; chiefly a. derivatives from the adjectives in I, as bicleavage (cf. bicleft in 2), bicoloration (cf. L. bicolor and bicoloured in 1), bivocalize v.; but also b. substantives formed after Latin analogies, in which bi- has the force of ‘double, two’; as bimillionaire, the owner of property valued at two millions of money; binomenclature, double naming; biprong, a two-pronged fork.a.1847–9Todd Cycl. Anat. & Phys. IV. 676/2 A *bicleavage of the azygos ventral rays.1877Coues Fur Anim. iv. 120 [The] animal..resumes its *bicoloration.b.1838New Month. Mag. LIV. 314 The millionaire..becomes a *bi-millionaire.1873Tristram Moab vii. 120 Another instance of *binomenclature, a duplicate name occurring on the east side.1872M. Collins Pr. Clarice I. xii. 114 The ancient *biprong of steel.III. Chem. Substantives and adjectives, in which bi- signifies the presence in a compound of twice that amount (usually two equivalents) of the acid, base, etc. indicated as present by the word to which it is prefixed. Thus carbonate of soda was viewed as containing one equivalent of carbonic acid, bicarbonate of soda as containing two. In recent chemical nomenclature, bi- has been systematically superseded by di-.1863Watts Dict. Chem. I. 584 *Bi-compounds: see Di⁓compounds.1819Brande Chem. v. §306 *Bicarbonate of Potassa is formed by passing a current of carbonic acid into a solution of the subcarbonate.1869Roscoe Elem. Chem. 210 The *bicarbonate [of soda] is chiefly used..for the production of refreshing drinks.1826Henry Elem. Chem. II. 45 The second sulphuret, or *bi-sulphuret of tin.1850Daubeny Atom. Th. x. (ed. 2) 342 *Bisulphuretted hydrogen is..decomposed by the action of alkalies.1863Tyndall Heat i. 14, I wet a pellet of cotton-wool with liquid *bi⁓sulphide of carbon.1879G. Gladstone in Cassell's Techn. Educ. IV. 213/1 Tartar emetic—the *bitartrate of antimony and potash.

bi-

word-forming element meaning "two, twice, double, doubly, once every two," etc., from Latin bi- "twice, double," from Old Latin dvi- (cognate with Sanskrit dvi-, Greek di-, Old English twi- "twice, double"), from PIE root *dwo- "two." Nativized from 16c. Occasionally bin- before vowels; this form originated in French, not Latin, and might be partly based on or influenced by Latin bini "twofold" (see binary).

bi- /bʌɪ/ prefix. Often bin- /bɪn/ before a vowel (cf. bis-).

ORIGIN: Latin (earlier dui-, cogn. with Greek di-², Sanskrit dvi-) = twice, doubly, having two, two-.

Used in words adopted from Latin and in English formations modelled on these, and as a productive prefix, forming (a) adjectives (and corresp. adverbs etc.) from adjectives or adverbs, with the senses ‘having or involving two’, as bicoloured, bilateral, bimanual, binaural, ‘doubly, in two ways’, as biconcave, bipyramidal, (Botany & Zoology) ‘twice over, divided into similarly divided parts’, as bipinnate, ‘lasting for two, appearing every two’, or (with resulting ambiguity) ‘appearing twice in’, as biannual, biennial, bimonthly, and ‘joining two’, as biparietal;(b) nouns from nouns with the sense ‘double, thing having two’, as bilayer, biplane; in Chemistry forming names of salts having a doubled proportion of acid to base radicals, as bicarbonate, binoxalate, bisulphate, or of molecules formed from two identical radicals, as biphenyl.

bi-

prefix.

a twice a _____: Biannual = twice a year.

b once every two _____: Bimonthly = once every two months.

doubly _____: Bipinnate = doubly pinnate.

two _____s: Bisect = divide into two parts. Bicuspid = two points (of teeth).

having two _____: Biped = having two feet.

Also, sometimes bin- before vowels.

[< Latin bi- < bis twice]

Bi (no period)

bismuth (chemical element).

bi

by, adjective.

Slang. attracted to both sexes; bisexual.

bi-
I. prefix
Etymology: Middle English, from Latin; akin to Old English twi- — more at twi-
1.
a. : two
  < bimuscular >
  < bicycle >
  < biracial >
b. : lasting two : coming or occurring every two
  < biennial >
  < bimonthly >
  < biweekly >
c. : into two parts
  < bisect >
2.
a. : twice : doubly : on both sides
  < biconic >
  < biconvex >
  < biserrate >
b. : coming or occurring two times
  < bidiurnal >
  < biquarterly >
  < biweekly >
— often disapproved in this sense because of the likelihood of confusion with sense 1b; compare semi-
3. anatomy : between, involving, or affecting two (specified) symmetrical parts
< bigonial >
< bi-iliac >
4. chemistry
a. : containing one (specified) constituent in double the proportion of the other constituent or in double the ordinary proportion — especially in names of acid salts formed with twice as much acid as is required for a normal salt
  < biurate >
b. : di- 2 — especially in names of organic compounds to denote the doubling of a radical or molecule
  < bitolyl >
  < biphenol >
II. combining form
or bio-
Etymology: Greek, from bios mode of life — more at quick
1. : life
< bioblast >
: living organisms or tissue
< biopsy >
< biodynamics >
2. : biology : biological
< biopsychology >
III. combining form
or bio-
: biographical
< biopic >
: biographical and
< biocritical >

bi-

Etymology

From Latin bis (“twice”).

Prefix

Latin number prefix
Previous:	uni-
Next:	tri-

two
(chemistry, proscribed) half

Usage notes

In an old, common method used to indicate the presence of an acidic hydrogen, sodium hydrogen sulfate is called "sodium bisulfate" and sodium hydrogen carbonate is called "sodium bicarbonate". This method is not recommended by IUPAC and does not denote a “doubling up” of a specific group, which is reserved for the Greek prefix di-, as in carbon dioxide (“CO₂”).

The prefix bi in the older system comes from the observation that there is two times as much carbonate (CO₃) in sodium bicarbonate (NaHCO₃) and other bicarbonates as in sodium carbonate (Na₂CO₃) and other carbonates.

Synonyms

di-

duo-

Derived terms

English words prefixed with bi-

bi

biannual

biautomaton

biceps

bichrome

bicolor

biconvex

bicornuate

bicycle

bicyclic

bicylindrical

bidentate

bidirectional

biennial

bifacial

bifocals

bijugate

bilabial

bilabiate

bilanguage

bilateral

bilinear

bilingual

billion

bilobate

bilogarithmic

bilogarithmical

bimanual

bimester

bimetal

bimonthly

binary

binomial

biped

bipod

biplane

bipolar

bireme

birefringent

birotate

biscuit

bisect

bisection

bisector

biserrate

bisexual

bisexuality

bitartrate

bivalve

biweekly

前缀：bi- 表示"两个, 两"

biweekly 双周刊（bi+week星期+ly→两星期）

bilingual 双语种的（bi+lingu语言+al→双语的）

biennial 两年一次的（bi+enn年+ial→两年〔一次〕的）

biannual 一年两次的（bi+ann[年]+ual→一年两次的）

前缀：bi- 两、二

biweekly 双周刊

bilingual 两种语言的

bicolour 两色的

bimonthly 双月刊

bisexual 两性的

bipolar 两极的，双向的

biplanc 双翼飞机

bicycle 自行车

bimetal 双金属

biform 有二形的

bilateral 双边的

bifacial 两面一样的

前缀：bi-

【词根含义】：两,二

【词根来源】：来源于拉丁语bi-。

【同源单词】：biannual, bicentennial, bicorn, bicycle, biennial

bi-1 or (sometimes before a vowel) bin-

combining form

Origin

bi-2

combining form

bio- or (before a vowel) bi-

combining form

Origin

bi-1

bi-2

bi-

Etymology

Prefix

Usage notes

Synonyms

Derived terms

前缀：bi- 表示"两个, 两"

前缀：bi- 两、二

前缀：bi-

bi-¹ or (sometimes before a vowel) bin-

bi-²

bi-¹

bi-²