Wiktionary
green alga
n. (context biology English) Any of very many organisms, of the division ''Chlorophyta'', that grow in damp places; a chlorophyte
Usage examples of "green alga".
Third: the ship's colony of Chlorella, the blue-green alga housed in many miles of transparent plastic tubing in what used to be the hold of the Argo, irradiated by fluorescent lamps and constantly in circulation in the nutrient bath in which it grew.