molehill n. + Add to list US //ˈmoʊɫˌhɪɫ// UK //mˈəʊlhɪl// mole·hill EtymologyOrigin From mole + hill. Idioms2 entries01make a mountain out of a molehillTo treat a problem as greater than it is; to blow something out of proportion; to exaggerate the importance of something trivial.02molehill mountaineerA person who habitually exaggerates or overemphasizes minor issues.