Definition of "undauntable" [un•daunt•a•ble]

• Not admitting of discouragement: undauntable heroism; undauntable optimism. (adjective)

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.

• "Ms. Swinton says that from the moment she met Mr. Guadagnino, she knew she was dealing with an artist who knew exactly what he wanted, adding, "he's a very undauntable person.""
• "The proof of this, so often and so tragically forgotten, is that the costs of providing an undauntable defense, whatever they may be, pale before blood and defeat."
• "His lemming-like followers apparently admire that undauntable confidence, while they ignore the cliff ahead."