Old English willian "to determine by act of choice," from will (n.). From mid-15c. as "dispose of by will or testament." Often difficult to distinguish from will (v.1).

Old English *willan, wyllan "to wish, desire; be willing; be used to; be about to" (past tense wolde), from Proto-Germanic *willjan (source also of Old Saxon willian, Old Norse vilja, Old Frisian willa, Dutch willen, Old High German wellan, German wollen, Gothic wiljan "to will, wish, desire," Gothic waljan "to choose").

The Germanic words are from PIE root *wel- (2) "to wish, will" (source also of Sanskrit vrnoti "chooses, prefers," varyah "to be chosen, eligible, excellent," varanam "choosing;" Avestan verenav- "to wish, will, choose;" Greek elpis "hope;" Latin volo, velle "to wish, will, desire;" Old Church Slavonic voljo, voliti "to will," veljo, veleti "to command;" Lithuanian velyti "to wish, favor," pa-velmi "I will," viliuos "I hope;" Welsh gwell "better").

Compare also Old English wel "well," literally "according to one's wish;" wela "well-being, riches." The use as a future auxiliary was already developing in Old English. The implication of intention or volition distinguishes it from shall, which expresses or implies obligation or necessity. Contracted forms, especially after pronouns, began to appear 16c., as in sheele for "she will." In early use often -ile to preserve pronunciation. The form with an apostrophe ('ll) is from 17c.

Old English will, willa "mind, determination, purpose; desire, wish, request; joy, delight," from Proto-Germanic *wiljon- (source also of Old Saxon willio, Old Norse vili, Old Frisian willa, Dutch wil, Old High German willio, German Wille, Gothic wilja "will"), related to *willan "to wish" (see will (v.1)). The meaning "written document expressing a person's wishes about disposition of property after death" is first recorded late 14c.

Old English godes willan "state of wishing well to another;" see good (adj.) + will (n.). Meaning "cheerful acquiescence" is from c. 1300. In the commercial sense "degree of favor enjoyed through patronage of customers" from 1570s.

also will power, 1847, from will (n.) + power (n.).

early 14c., present-participle adjective from will (v.1). Old English had -willendliche in compounds. Related: Willingly; willingness.

c. 1600, contraction of will I, nill I, or will he, nill he, or will ye, nill ye, literally "with or without the will of the person concerned." See nill + will (v.1).

contraction of will not, 1610s in plays. See will. Earlier as wynnot (mid-15c.), later wonnot (1580s).

also wilful, c. 1200, "strong-willed," usually in a bad sense, "obstinate, unreasonable," from will (n.) + -ful. From late 14c. as "eager" (to do something). Mid-14c., of actions, "done on purpose, intentional, due to one's own will." Related: Willfullness.

"volition in the weakest form; an indolent or inactive wish," 1610s, from Medieval Latin stem of velleitas (from Latin velle "to wish, will;" see will (v.)) + -ity.