a. 1. Not grateful; not thankful for favors; making no returns, or making ill return for kindness, attention, etc.; ingrateful. South. [ 1913 Webster ]
2. Unpleasing; unacceptable; disagreeable; as, harsh sounds are ungrateful to the ear. [ 1913 Webster ]
-- Un*grate"ful*ly, adv. -- Un*grate"ful*ness, n. [ 1913 Webster ]