ˌfēəˈthamnēˌän noun
Usage: capitalized
Etymology: New Latin, from phaeo- + Greek thamnion little bush, diminutive of thamnos bush — more at thamn-
: a genus (the type of the family Phaeothamniaceae) of rare yellow green algae growing upon other algae and having a definite central axis and ascending lateral filaments made up of cylindrical to subovoid cells