| Noun | 1. | Chlamydomonadaceae - green algae some of which are colored red by hematochrome protoctist family - any of the families of Protoctista order Volvocales, Volvocales - chiefly freshwater green algae; solitary or colonial Chlamydomonas, genus Chlamydomonas - type genus of the Chlamydomonadaceae; solitary doubly-flagellated plant-like algae common in fresh water and damp soil; multiply freely; often a pest around filtration plants |