Old English cyðð "kinship, relationship; kinsfolk, fellow-countrymen, neighbors; native country, home; knowledge, acquaintance, familiarity," from cuð "known," past participle of cunnan "to know" (see can, v.). Cognate with Old High German chundida. The alliterative phrase kith and kin (late 14c.) originally meant "country and kinsmen" and is almost the word's only survival.