Not feeling or exhibiting gratitude, thanks, or appreciation.
Not agreeable or pleasant; repellent: "I will not perform the ungrateful task of comparing cases of failure” ( Abraham Lincoln).
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.