We found 9 dictionaries that define the word underachieving:

General (8 matching dictionaries)

1. underachieving: Merriam-Webster
2. underachieving: Collins English Dictionary
3. underachieving: Vocabulary.com
4. Underachieving, underachieving: Wordnik
5. underachieving: Cambridge Advanced Learner's Dictionary
6. underachieving: Wiktionary
7. underachieving: Dictionary.com
8. underachieving: TheFreeDictionary.com

Medicine (1 matching dictionary)

9. underachieving: Merriam-Webster Medical Dictionary

(Note: See underachieve as well.)

Definitions from Wiktionary (underachieve) ▸ verb:  To achieve less than expected; to fail to fulfil one's potential. ▸ Also see underachieve ▸ Words similar to underachieving ▸ Usage examples for underachieving ▸ Idioms related to underachieving ▸ Wikipedia articles (New!) ▸ Words that often appear near underachieving ▸ Rhymes of underachieving ▸ Invented words related to underachieving