endothermic vs. exothermic

endothermic vs. exothermic: What’s the difference?

Endothermic and exothermic are used in chemistry to describe chemical reactions—specifically, to indicate whether heat is absorbed or released (-thermic refers to heat). Endothermic reactions are those in which heat is absorbed (endo- means “in”). Exothermic is the opposite—exothermic reactions are those in which heat is given off (exo- means “out”).