In figurative use, something of great size.
make a mountain out of a molehill lay unnecessary stress on a small matter.
mountain in labour great effort expended on little outcome, an allusion to the words of the Roman poet Horace (65–8 bc) in his Ars Poetica, ‘Parturient montes, nascetur ridiculus mus [Mountains will go into labour, and a silly little mouse will be born].’
Mountain State an informal name for Vermont.
See also if the mountain will not come to Mahomet, mountains.