coal 
/ˈkoʊl/ noun
plural coals /ˈkoʊl/ noun 1 [noncount] : a black or brownish-black hard substance within the earth that is used as a fuel
▪ a bin of coal ▪ The furnace burns coal. ▪ a lump of coal — often used before another noun ▪ a coal bin/mine/bed/stove ▪ the coal industry 2 [count] a : a piece of coal or charcoal especially when burning
▪ When the coals are red, they are very hot.
b US : a glowing piece of wood from a fire : ember
▪ I toasted one last marshmallow over the coals of the campfire.
▪ a bin of coal ▪ The furnace burns coal. ▪ a lump of coal — often used before another noun ▪ a coal bin/mine/bed/stove ▪ the coal industry
▪ When the coals are red, they are very hot.
b US : a glowing piece of wood from a fire : ember
▪ I toasted one last marshmallow over the coals of the campfire.
carry/take coals to Newcastle
Brit : to take something to a place where it is not needed because a large amount of it is already there
haul/rake (someone) over the coals
informal : to criticize (someone) very severely
▪ I arrived late for the meeting and was immediately hauled over the coals by my boss.
▪ I arrived late for the meeting and was immediately hauled over the coals by my boss.
