n.
Pronunciation: ˌ r ī -b ə - ' fl ā -v ə n, ' r ī -b ə - ˌ
Function: noun
Etymology: International Scientific Vocabulary ribo- + Latin flavus yellow ― more at BLUE
Date: 1935
: a yellow crystalline compound C 17 H 20 N 4 O 6 of the vitamin B complex that occurs both free (as in milk) and combined (as in liver) as a component of coenzymes (as FMN) which are essential to normal metabolism ― called also vitamin B 2