"prone to indulge in sensuality, lustful, lewd," c. 1300, probably from lecher + -ous; or else from rare Old French adjective lecheros. The nativized form is lickerish. Related: Lecherously; lecherousness.
"lustful man, man given to excessive sexual indulgence," late 12c., from Old French lecheor (Modern French lécheur) "one living a life of debauchery," especially "one given to sexual indulgence," literally "licker," agent noun from lechier "to lick;" also "to live in debauchery or gluttony," from Frankish *likkon or some other Germanic source, from Proto-Germanic *likkojan "to lick" (from PIE root *leigh- "to lick"). The Old French feminine form was lechiere. Middle English, meanwhile, had lickestre "female who licks;" figuratively "a pleasure seeker," literally "lickster," with -ster. In 18c. sometimes leacher (Bailey), along with leacherous, leachery.
word-forming element making adjectives from nouns, meaning "having, full of, having to do with, doing, inclined to," from Old French -ous, -eux, from Latin -osus (compare -ose (1)). In chemistry, "having a lower valence than forms expressed in -ic."
"fond of delicious fare," c. 1500, a corruption (as if from licker or liquor + -ish) of Middle English likerous "pleasing to the palate" (late 13c.), from Anglo-French *likerous, Old French licherous (see lecherous). Unlike the French word, it generally kept close to its literal sense. Related: Lickerishly; lickerishness.
<a href="https://www.etymonline.com/word/lecherous">Etymology of lecherous by etymonline</a>
Harper, D. (n.d.). Etymology of lecherous. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/lecherous