Origin: ME engreinen < OFr engrainer, to dye scarlet < en- (see en-) + graine, seed, cochineal dye; assoc. in both Fr & E with grain (texture): see grain
See engrain in American Heritage Dictionary 4
transitive verb en·grained, en·grain·ing, en·grains
Origin: Middle English engreinen, to dye with cochineal or kermes
Origin: , from Old French engrainer
Origin: : en-, causative pref.; see en-1
Origin: + graine, grain; see grain.
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