noun, plural pro·to·ne·ma·ta [proh-tuh-nee-muh-tuh] /ˌproʊ təˈni mə tə/. Botany.
  1. a primary, usually filamentous structure produced by the germination of the spore in mosses and certain related plants, and from which the leafy plant which bears the sexual organs arises as a lateral or terminal shoot.

Origin of protonema

1855–60; < New Latin < Greek prōto- proto- + nêma thread
Related formspro·to·ne·mal, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for protonemata


noun plural -nemata (-ˈniːmətə)
  1. a branched threadlike structure that grows from a moss spore and eventually develops into the moss plant
Derived Formsprotonemal or protonematal (ˌprəʊtəˈniːmətəl, -ˈnɛmətəl), adjective

Word Origin for protonema

C19: from New Latin, from proto- + Greek nema thread
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

protonemata in Science


Plural protonemata (prō′tə-nēmə-tə, -nĕmə-)
  1. The green filamentous or flat, thallus-like structure that grows from the germinated spores of liverworts and mosses and eventually gives rise to a mature gametophyte.
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