Definition from Wiktionary, the free dictionary
thankless (not comparable)
- (of a task) not appreciated or rewarded
2014 November 14, Stephen Halliday, “Scotland 1-0 Republic of Ireland: Maloney the hero”, The Scotsman:
- In a raucous atmosphere, it was an unforgiving and physical contest from the start. Grant Hanley conceded the first free-kick within the opening 20 seconds, setting the tone for a busy and thankless evening for Serbian referee Milorad Mazic.
- (of a person) ungrateful or unappreciative