from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A small mound of loose earth raised by a burrowing mole.
- idiom make a mountain out of a molehill To exaggerate a minor problem.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A small mound of earth created by a mole's burrowing underneath the surface of the ground.
from the GNU version of the Collaborative International Dictionary of English
- n. A little hillock of earth thrown up by moles working under ground; hence, a very small hill, or an insignificant obstacle or difficulty.
from The Century Dictionary and Cyclopedia
- n. A little hill, hillock, mound, or ridge of earth thrown up by moles in burrowing underground.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a mound of earth made by moles while burrowing
From mole + hill. (Wiktionary)