adjective
- unappreciative; not displaying gratitude; not giving due return or recompense for benefits conferred: ungrateful heirs.
- unpleasant; distasteful; repellent: an ungrateful task.
adjective
- not grateful or thankful
- unrewarding or unpleasant; thankless
- (of land) failing to increase fertility in response to cultivation
adj.1550s, from un- (1) “not” + grateful. Related: Ungratefully.