dioptre
noun/daɪˈɒptə(r)/
/daɪˈɑːptər/
(US English diopter)
(physics)- a unit for measuring the power of a lens to refract light (= make it change direction)Word Originlate 16th cent. (originally as diopter): from French, from Latin dioptra, from Greek, from di- ‘through’ + optos ‘visible’. The term was used in the early 17th cent. to denote an ancient form of theodolite; the current sense dates from the late 19th cent.
Want to learn more?
Find out which words work together and produce more natural sounding English with the Oxford Collocations Dictionary app.
Check pronunciation:
dioptre