n.
Pronunciation: -r ē - ˌ ak-t ə - ' v ā -sh ə n
Function: noun
Date: 1949
: repair of DNA (as of a bacterium) especially by a light-dependent enzymatic reaction after damage by ultraviolet irradiation
– pho · to · re · ac · ti · vat · ing \ - ' ak-t ə - ˌ v ā -ti ŋ \ adjective