Among the many words we mishear (or perhaps hear “mispronounced”) is ingrain and ingrained. Because of this, many spell it engrain and engrained.
Ingrain means to impress deeply while ingrained means impressed deeply, as in The habit had been long ingrained in Aunt Dawn’s morning ritual.
Because engrain/engrained are increasingly used, many dictionaries now list it as acceptable variants. Still, their use is rarer than ingrain/ingrained.
Bottom line: Go with ingrain/ingrained until it becomes the rarely used variant of engrain/engrained.
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My name is Rob Bignell. I’m an affordable, professional editor who runs Inventing Reality Editing Service, which meets the manuscript needs of writers both new and published. I also offer a variety of self-publishing services. During the past decade, I’ve helped more than 300 novelists and nonfiction authors obtain their publishing dreams at reasonable prices. I’m also the author of the 7 Minutes a Day… writing guidebooks, four nonfiction hiking guidebook series, and the literary novel Windmill. Several of my short stories in the literary and science fiction genres also have been published.