Definition of protonema
plural pro·to·ne·ma·taplay \-ˈnē-mə-tə, -ˈne-\
: the primary usually filamentous thalloid stage of the gametophyte in mosses and in some liverworts comparable to the prothallus in ferns
Origin of protonema
New Latin protonemat-, protonema, from prot- + Greek nēma thread — more at nemat-
First Known Use: 1857
Learn More about protonema
Britannica.com: Encyclopedia article about "protonema"
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