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definitions

de-excite

or de·ex·cite

[dee-ik-sahyt]Physics.
verb (used with object), de-ex·cit·ed, de-ex·cit·ing.
  1. to cause (an atom) to fall from an excited energy level to a lower energy level.
verb (used without object), de-ex·cit·ed, de-ex·cit·ing.
  1. to become de-excited.

Origin of de-excite

First recorded in 1960–65
Related formsde-ex·ci·ta·tion, de·ex·ci·ta·tion, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018