means Oxygen is the colorless, odorless gas (element number 8) that makes up about a fifth of the air, sustains breathing, and feeds fire and rust.

from Coined in the late 18th century by the French chemist Lavoisier from Greek 'oxys' (sharp, acid) plus '-genes' (forming, producing) — literally 'acid-maker,' because he wrongly believed the gas was the essential ingredient of all acids. The chemistry turned out to be off, but the name stuck, so we breathe a word built on a beautiful mistake.