in former classifications: a division or other group comprising the algae, fungi, and lichens
b
in some especially former classifications: a division or other group comprising unicellular plants and including bacteria, yeasts, slime molds, blue-green algae, and various simple green algae—often used as a term of convenience rather than strict taxonomy compare protista
c
in some classifications: a division comprising unicellular and noncellular organisms and including blue-green algae, bacteria, rickettsias and related organisms, and viruses—used chiefly in bacteriological taxonomy
Word History
Etymology
New Latin, from prot- + -phyta
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