Testosterone

How to spell testosterone

12 letters · 4 syllables

How to pronounce testosterone

Say the part in capitals loudest.

What does testosterone mean?

1. nounThe principal male sex hormone, a steroid that regulates muscle growth, bone density, and the development of male characteristics.

Testosterone in a sentence

• The clinic measured his testosterone levels with a simple blood test.

• Low testosterone can cause fatigue and reduced muscle mass in older men.

Where does testosterone come from?

Language of origin: Latin

Testosterone is a twentieth-century scientific coinage, assembled in 1935 when the hormone was first isolated and synthesised by researchers working on the steroids produced by the testes. The name blends three elements: 'testo-', from the Latin testis meaning 'testicle' (the organ where it was found to be produced), 'ster-' from 'sterol', a class of steroid alcohols whose own name comes from the Greek stereos meaning 'solid', and the suffix '-one', the standard chemical ending that marks a ketone, a particular type of molecule. So the word literally announces its own chemistry: a ketone-type steroid from the testis. The same Latin testis, which curiously also gave English 'testify' and 'testimony' (a witness being one who bears testament), survives in the medical word 'testicle'. Knowing the word is built from testis plus sterol plus -one explains the slightly awkward 'tos-ter-one' spelling in the middle, which is otherwise easy to slur in speech.

How the word is built

• testo- (from testis, testicle)
• ster- (from sterol, a steroid alcohol)
• -one (chemical suffix marking a ketone)