lumen

/loomen/

  • noun Physics the SI unit of luminous flux, equal to the amount of light emitted per second in a unit solid angle of one steradian from a uniform source of one candela.

  — ORIGIN Latin, ‘light’.

Perform another search of the Compact Oxford English Dictionary

About this dictionary
The Compact Oxford English Dictionary of Current English contains 145,000 words, phrases, and definitions.
Find out more about Oxford's range of English dictionaries
Sign up for the AskOxford Word of the Day

Search the Little Oxford Dictionary of Quotations
Search the Concise Dictionary of First Names