Oxygen

How to spell oxygen

6 letters · 3 syllables

How to pronounce oxygen

Say the part in capitals loudest.

What does oxygen mean?

1. nounA colourless, odourless gas that makes up about a fifth of the air and is essential for breathing and combustion.

Oxygen in a sentence

• The climbers carried bottled oxygen for the final ascent.

• Divers monitor their oxygen levels carefully during a long descent.

Where does oxygen come from?

Language of origin: Greek

Oxygen was coined in the 1780s by the French chemist Antoine Lavoisier, who built it from two Greek elements: oxys, meaning 'sharp' or 'acid', and the suffix -genes, meaning 'producing' or 'born of'. He literally intended the name to mean 'acid-former', because he wrongly believed at the time that this newly identified gas was an essential ingredient of every acid. The French form oxygène passed quickly into English in the late eighteenth century as scientists across Europe adopted the new chemical naming system. The same Greek oxys survives in words like 'oxymoron', where contradictory ideas are placed sharply together, and the -gen ending recurs in 'hydrogen' and 'nitrogen'. The spelling trap is the soft middle: that unstressed 'y' and the 'gen' that sounds like 'jen', both of which tempt writers toward phonetic respellings.

How the word is built

• oxy- (from Greek oxys: sharp, acid)
• -gen (from gen-: producing, generating)