brown algae

pl n

any algae of the phylum Phaeophyta, such as the wracks and kelps, which contain a brown pigment in addition to chlorophyll
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012