W2S3 [kəul US koul] n
[: Old English; Origin: col]
1.) [U]
a hard black mineral which is dug out of the ground and burnt to produce heat
Put some coal on the fire.
the coal mining industry
a lump of coal
2.) [C usually plural]
a piece of coal, especially one that is burning
Red hot coals glowed in the grate.
3.) [C usually plural] AmE
a piece of wood or coal that is burning
Grill over hot coals for four to five minutes.
4.) carry/take coals to Newcastle
BrE to take something to a place where there is already plenty of it available
5.) haul/rake/drag sb over the coals
to speak angrily to someone because they have done something wrong

Dictionary of contemporary English. 2013.