engrave 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.

"to engrave," Old English grafan "to dig, dig up; engrave, carve, chisel" (medial -f- pronounced as "v" in Old English; past tense grof, past participle grafen), from Proto-Germanic *grabanan (source also of Old Norse grafa "to dig; engrave; inquire into," Old Frisian greva, Dutch graven "to dig, delve," Old High German graban, German graben, Gothic graban "to dig, carve"), from the same source as grave (n.). Its Middle English strong past participle, graven, is the only part still active, the rest of the word supplanted by its derivative, engrave.