bioluminescence Syllabification: (bi·o·lu·mi·nes·cence)Pronunciation: /ˌbīōˌlo͞oməˈnesəns/Definition of bioluminescence noun the biochemical emission of light by living organisms such as fireflies and deep-sea fishes. the light emitted by organisms such as fireflies and deep-sea fishes. Derivatives bioluminescentPronunciation: /-ˈnesənt/ adjective bioluminescence in other Oxford dictionaries Definition of bioluminescence in the British & World English dictionary