pro·​to·​ne·​ma | \ ˌprō-tə-ˈnē-mə How to pronounce protonema (audio) \
plural protonemata\ ˌprō-​tə-​ˈnē-​mə-​tə How to pronounce protonemata (audio) , -​ˈne-​ \

Definition of protonema

: the primary usually filamentous thalloid stage of the gametophyte in mosses and in some liverworts comparable to the prothallus in ferns

Other Words from protonema

protonemal \ ˌprō-​tə-​ˈnē-​məl How to pronounce protonemal (audio) \ adjective
protonematal \ ˌprō-​tə-​ˈnē-​mə-​tᵊl How to pronounce protonematal (audio) , -​ˈne-​ How to pronounce protonematal (audio) \ adjective

First Known Use of protonema

1857, in the meaning defined above

History and Etymology for protonema

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

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The first known use of protonema was in 1857

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to mark by some ceremony or observation

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