Oxidation
Etymology
Built from "oxygen" — coined by Lavoisier from Greek "oxys" (sharp, acid) plus "-genes" (forming), because he wrongly believed oxygen was the essential ingredient of all acids. Chemistry later generalized oxidation to any loss of electrons, oxygen or not.
noun · /ok-sih-DAY-shun/
A chemical reaction in which a substance loses electrons — classically, combines with oxygen — as in rusting, burning, and browning.
What it names
The common thread linking rust on iron, a browning apple, a burning log, and even the way your cells extract energy from food.
Example
The apple slice browns within minutes as oxidation sets in; a squeeze of lemon juice slows it down.
Related idea
Oxidation is often sped along by a catalyst or, in living cells, an enzyme, which lowers the barrier to the reaction without being consumed by it.