The noun ingrate comes for the Latin word ingratus, a combination of in-, meaning “not,” and gratus, or “grateful.” That pretty much sums up an ingrate: not grateful. It describes someone who tends to act this way in general, rarely acknowledging others' generosity, or even worse, seeming to expect special treatment. You can tell someone is an ingrate by what isn't said: "thank you" and "I appreciate what you've done for me."