In thermodynamics, the term endothermic process describes a process or
reaction in which the system [blank_start]absorbs[blank_end] energy from its surroundings;
usually, but not always, in the form of [blank_start]heat.[blank_end]
The term was coined by Marcellin Berthelot from the Greek roots endo-, derived from the word
"endon" (ἔνδον) meaning "[blank_start]within[blank_end]" and the root "therm" (θερμ-) meaning "hot."
Breaking bonds (overcoming the force of attraction) requires [blank_start]energy[blank_end]. You have to put heat in - it is endothermic. This is why melting and boiling are [blank_start]endothermic[blank_end].