lax
adj.
c.1400, "loose" (in reference to bowels), from Latin laxus "wide, loose, open," figuratively "loose, free, wide," from PIE root *(s)leg- "to be slack, be languid" (cognates: Greek legein "to leave off, stop," lagos "hare," literally "with drooping ears," lagnos "lustful, lascivious," lagaros "slack, hollow, shrunken;" Latin languere "to be faint, weary," languidis "faint, weak, dull, sluggish, languid"). Of rules, discipline, etc., attested from mid-15c.
n.
"salmon," from Old English leax (see lox).
词根：lax = loose, 表示“松”
lax a. 松弛的
laxative n. 缓泻药（lax+ative→放松的[药]→泻药）
laxity n. 松弛（lax+ity）
relax v. 放松，宽心（re重新+lax→重新松开→放松）
relaxation n. 休息；娱乐（relax的名词）
〔李〕[lax] a.宽松的； 松弛的； 不严格的 ←lax,leas (L laxus)=loose 松弛的