Word Study
exothermic
CIDE DICTIONARY
exothermic, a. [Pref. exo- + thermic.].
Characterized by, or formed with, evolution of heat; as, an exothermic reaction; -- opposed to endothermic . [Webster 1913 Suppl.]
OXFORD DICTIONARY
exothermic, adj. (also exothermal) esp. Chem. occurring or formed with the evolution of heat.
Derivative
exothermally adv. exothermically adv.
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