Reflex

How to spell reflex

6 letters · 2 syllables

How to pronounce reflex

Say the part in capitals loudest.

What does reflex mean?

1. nounAn involuntary, automatic response of the body to a stimulus.
2. adjectiveOccurring automatically and without conscious thought.

Reflex in a sentence

• noun

  The doctor tapped his knee to test the reflex.

• adjective

  Pulling your hand from a hot stove is a reflex action.

• noun

  Blinking when something flies at your face is a natural reflex.

• adjective

  The goalkeeper made a brilliant reflex save in the final minute.

Where does reflex come from?

Language of origin: Latin

This word descends from the Latin reflexus, the past participle of reflectere, which literally meant 'to bend back' or 'to turn back', formed from re- 'back' and flectere 'to bend'. The same flectere root sits behind a whole family of English words, including 'flexible', 'deflect', and 'reflect', all of which carry that core idea of bending or turning. English adopted 'reflex' in the 1500s, at first in the sense of light or heat being bent or thrown back from a surface. By the nineteenth century physiologists had borrowed it for the body's automatic 'bending back' of a stimulus into an immediate response, which is the meaning most people reach for today. Because the word ends in the unusual letter cluster -flex rather than the more familiar -flect of its cousin 'reflect', the spelling trap is simply remembering that the action 'bends back' but the noun stops at the x.

How the word is built

• re- (back)
• flex (to bend, from Latin flectere)