Longman Dictionary of Contemporary English
coal mine
noun
EXAMPLES FROM CORPUS
▪ Cerrejon is the second largest open pit coal mine in the world.
▪ They used to live in the county of Saepiol in North Hamgyong, where the father worked in the Aoji coal mine.
Wiktionary
coal mine
alt. A mine#Noun from which coal ore or coal minerals are mined. n. A mine#Noun from which coal ore or coal minerals are mined.
WordNet
coal mine
n. a mine where coal is dug from the ground [syn: coalpit]