• IPA: /ˈɹeɪdi.əns/

radiance

1. The quality of being radiant, shining, bright or splendid.
   • 1667, John Milton, “Book 7”, in Paradise Lost. A Poem Written in Ten Books, London: Printed [by Samuel Simmons], and are to be sold by Peter Parker […] [a]nd by Robert Boulter […] [a]nd Matthias Walker, […], OCLC 228722708 ↗; republished as Paradise Lost in Ten Books: The Text Exactly Reproduced from the First Edition of 1667: […], London: Basil Montagu Pickering […], 1873, OCLC 230729554 ↗:

     Girt with omnipotence, with radiance crowned.

2. (physics) The flux of radiation emitted per unit solid angle in a given direction by a unit area of a source.

• Italian: radianza
• Russian: сия́ние

• Russian: излуче́ние