westerly adv.

"toward or of the west," late Old English westerne "western, westerly, coming from the west," from west + -erne, suffix denoting direction. The noun meaning "book or movie about the Old West" is first attested 1909. Westerner is from 1837 as "person from the U.S. West," 1880 as "Euro-American," as opposed to Oriental.

common adverbial suffix, forming from adjectives adverbs signifying "in a manner denoted by" the adjective, Middle English, from Old English -lice, from Proto-Germanic *-liko- (cognates: Old Frisian -like, Old Saxon -liko, Dutch -lijk, Old High German -licho, German -lich, Old Norse -liga, Gothic -leiko); see -ly (1). Cognate with lich, and identical with like (adj.).

Weekley notes as "curious" that Germanic uses a word essentially meaning "body" for the adverbial formation, while Romanic uses one meaning "mind" (as in French constamment from Latin constanti mente). The modern English form emerged in late Middle English, probably from influence of Old Norse -liga.