Underwhelm is a word used to describe a lack of excitement or enthusiasm. Antonyms for this word would be something that signifies excitement, enthusiasm, or an overwhelming feeling. Words like awe, inspire, amaze, leave spellbound, or awe-stricken can be used to describe situations that are the opposite of underwhelming. Antonyms for underwhelm can also be words such as captivate, enthrall, or fascinate, which implies a sense of enthusiasm and interest. Hence, to find antonyms of underwhelm, one must explore the words that symbolize feelings of excitement and overwhelming interest.