1520s, from French laxité, from Latin laxitatem (nominative laxitas) "width, spaciousness," from laxus "loose, lax" (see lax). An earlier noun was laxation (late 14c.). Laxness is from 1630s.
Entries linking to laxity
lax adj.
c. 1400, "loose" (in reference to bowels), from Latin laxus "wide, spacious, roomy," figuratively "loose, free, wide" (also used of indulgent rule and low prices), from PIE *lag-so-, suffixed form of root *sleg- "be slack, be languid."
In English, of rules, discipline, etc., from mid-15c. Related: Laxly; laxness. A transposed Vulgar Latin form yielded Old French lasche, French lâche. The laxists, though they formed no avowed school, were nonetheless condemned by Innocent XI in 1679.