"labor, toil," mid-13c., from Old French travail "work, labor, toil, suffering or painful effort, trouble; arduous journey" (12c.), from travailler "to toil, labor," originally "to trouble, torture, torment," from Vulgar Latin *tripaliare "to torture," from *tripalium (in Late Latin trepalium) "instrument of torture," probably from Latin tripalis "having three stakes" (from tria "three;" see three + palus "stake;" see pale, n.), which sounds ominous, but the exact notion is obscure. The verb is recorded from late 13c. in English, from the verb in Old French.