'blue-green alga' definitions:
Definition of 'blue-green alga'
From: GCIDE
- blue-green alga \blue"-green al"ga\ pl. {blue"-green al"gae} [from the color and resemblance to algae.] any of a group of photosynthetic microorganisms possessing characteristics of both bacteria and plants. When classed as bacteria, they are assigned to the Cyanobacteria; when classed as plants, they are assigned to the Cyanophyta. They are now known to be prokaryotic, and are usually called cyanobacteria in technical contexts. See cyanobacterium. [PJC]