plural noun

: a major category of lower plants: such as
in former classifications : a division or other group comprising the algae, fungi, and lichens
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
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


New Latin, from prot- + -phyta

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Dictionary Entries Near Protophyta

Cite this Entry

“Protophyta.” Dictionary, Merriam-Webster, Accessed 10 Dec. 2023.

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