Pronunciation: (un"dur-u-chēv'), [key]
—v.i., -a•chieved, -a•chiev•ing.
1. to perform, esp. academically, below the potential indicated by tests of one's mental ability or aptitude.
2. to perform below expectations or achieve less than expected, esp. by others.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.