encroach v.

word-forming element meaning "in; into," from French and Old French en-, from Latin in- "in, into" (from PIE root *en "in"). Typically assimilated before -p-, -b-, -m-, -l-, and -r-. Latin in- became en- in French, Spanish, Portuguese, but remained in- in Italian.

Also used with native and imported elements to form verbs from nouns and adjectives, with a sense "put in or on" (encircle), also "cause to be, make into" (endear), and used as an intensive (enclose). Spelling variants in French that were brought over into Middle English account for parallels such as ensure/insure, and most en- words in English had at one time or another a variant in in-, and vice versa.

c. 1200, "hook-shaped instrument or weapon; tool or utensil consisting of or having as an essential component a hook or curved piece of metal," from Old Norse krokr "hook, corner," cognate with Old High German kracho "hooked tool," of obscure origin but perhaps related to the widespread group of Germanic kr- words meaning "bent, hooked." If there was an Old English *croc it has not been found.

From late 14c. as "a bend or curved part;" late 15c. as "any bend, turn, or curve." From mid-15c. as "a shepherd's staff with a curved top." Meaning "swindler" is American English, 1879, from crooked in figurative sense of "dishonest, crooked in conduct" (1708). Crook "dishonest trick" was in Middle English, especially in reference to the wiles of the Devil.

mid-15c., "obtruding structure," from encroach + -ment, or an equivalent Old French compound.