blue green noun 3adjective 5forms 4 noun3 •A bluish green colour. •A blue-green alga.Blue-greens were the principal primary producers throughout the Proterozoic eon from 2.5 billion to 543 million years ago. — 2012 •An ecocapitalist; a person concerned with ecocapitalism. adjective5 •Of a color between blue and green; darker shades are called teal, lighter ones are cyan.The Lethrblaka's blood, to Eragon's astonishment, was a metallic blue-green, not unlike the verdigris that forms on aged copper. — 2008 •Of a bluish green colour. •Alternative form of blue-green. •Synonym of ecocapitalist; concerning ecocapitalism. •Synonym of ecocapitalist; Pertaining to ecocapitalism formsblue greens · blue-greens · more blue-green · most blue-green