ˌhed.ə(ˌ)rōˌkapˈsā(ˌ)lēz noun plural
Usage: capitalized
Etymology: New Latin
: an order of yellowish to brownish green algae (class Xanthophyceae) that form amorphous or arborescent palmelloid colonies containing an indefinite number of cells which are capable of reverting to a motile state directly or through zoospore formation — compare heterococcales , volvocales