c. 1400, from phrase put in dever (see endeavor (n.)). Related: Endeavored; endeavoring.
early 15c., "pains taken to attain an object," literally "in duty," from phrase put (oneself) in dever "make it one's duty" (a partial translation of Old French mettre en deveir "put in duty"), from Old French dever "duty," from Latin debere "to owe," originally, "keep something away from someone," from de- "away" (see de-) + habere "to have" (from PIE root *ghabh- "to give or receive"). One's endeavors meaning one's "utmost effort" is from late 15c.
also *ghebh-, Proto-Indo-European root meaning "to give or receive." The basic sense of the root probably is "to hold," which can be either in offering or in taking.
It forms all or part of: able; avoirdupois; binnacle; cohabit; cohabitation; debenture; debit; debt; dishabille; due; duty; endeavor; exhibit; exhibition; forgive; gavel; gift; give; habeas corpus; habiliment; habit; habitable; habitant; habitat; habitation; habitual; habituate; habituation; habitude; habitue; inhabit; inhibit; inhibition; malady; prebend; prohibit; prohibition; provender.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit gabhasti- "hand, forearm;" Latin habere "to have, hold, possess," habitus "condition, demeanor, appearance, dress;" Old Irish gaibim "I take, hold, I have," gabal "act of taking;" Lithuanian gabana "armful," gabenti "to remove;" Gothic gabei "riches;" Old English giefan, Old Norse gefa "to give."
1570s, "endeavor to gain the favor of by amorous attention," also "solicit, seek to win or attract," from court (n.), based on the sorts of behavior associated with royal courts. Related: Courted; courting.
c. 1600, "to build up from simple elements," from Latin elaboratus, past participle of elaborare "to labor, endeavor, struggle, work out" (see elaboration). Meaning "to work out in detail" is attested from 1610s. Related: Elaborated; elaborating.
1540s, "action of acquiring by effort, act of reaching by exertion," from French atteignement, from attaindre "to come up to, reach, attain, endeavor, strive" (see attain). The sense of "that which is attained, personal accomplishment" dates from 1670s.
c. 1300, "to try, endeavor, strive; test the quality of," from Anglo-French assaier, from assai (n.), from Old French assai, variant of essai "trial" (see essay (n.)). Related: Assayed; assaying.
1530s, "a putting forth of effort in some difficult or uncertain endeavor," from attempt (v.). The meaning "effort to accomplish something by violence" is from 1580s, especially as an assault on someone's life.