pro·​to·​ne·​ma ˌprō-tə-ˈnē-mə How to pronounce protonema (audio)
plural protonemata ˌprō-tə-ˈnē-mə-tə How to pronounce protonema (audio)
: the primary usually filamentous thalloid stage of the gametophyte in mosses and in some liverworts comparable to the prothallus in ferns
protonemal adjective
protonematal adjective

Word History


New Latin protonemat-, protonema, from prot- + Greek nēma thread — more at nemat-

First Known Use

1857, in the meaning defined above

Time Traveler
The first known use of protonema was in 1857

Dictionary Entries Near protonema

Cite this Entry

“Protonema.” Dictionary, Merriam-Webster, Accessed 27 May. 2024.

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