Entries linking to engraft
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.
"shoot inserted into another plant," late 15c. alteration of Middle English graff (late 14c.), from Old French graife "grafting knife, carving tool; stylus, pen," from Latin graphium "stylus," from Greek grapheion "stylus," from graphein "to write" (see -graphy). So called probably on resemblance of a stylus to the pencil-shaped shoots used in grafting. The terminal -t in the English word is not explained. Surgical sense is from 1871.