The Collaborative International Dictionary
Congo group
Congo group \Con"go group\ [From Congo red.] A group of artificial dyes with an affinity for vegetable fibers, so that no mordant is required. Most of them are azo compounds derived from benzidine or tolidine. Called also benzidine dyes.
Usage examples of "congo group".
In the Congo group are the Mundangs who lived beside the river 'Mayo-Kebbi'.