plural noun
Hy·​drach·​ni·​dae | \ -nəˌdē \

Definition of Hydrachnidae

in some classifications
: a large family of water mites (group Hydrachnellae) that includes all the common free-living mites of fresh water and a few parasites of the gills of mollusks and that is now usually broken up into numerous separate families

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History and Etymology for Hydrachnidae

New Latin, from Hydrachna, type genus (from hydr- + Greek achna, achnē foam, chaff) + -idae

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Cite this Entry

“Hydrachnidae.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Hydrachnidae. Accessed 20 Jan. 2021.

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