Meaning

noun a colorless gas (O3) soluble in alkalis and cold water; a strong oxidizing agent; can be produced by electric discharge in oxygen or by the action of ultraviolet radiation on oxygen in the stratospher

originFrom German Ozon, coined 1840 by Christian Friedrich Schönbein, from Ancient Greek ὄζον (ózon), neuter participle of ὄζω (ózō, “I smell”), in reference to its pungent odour. The “fresh air” sense is from an erroneous former belief that seaweed contains and releases ozone.

Etymology from Wiktionary, CC BY-SA 3.0