plural ctenidia
: the gill of a mollusk consisting typically of a respiratory structure that resembles a comb or feather, has a main stem with lateral lamellae, and is developed from the inner side of the mantle
distinguished from ceras
: a structure consisting of a row of spines resembling the teeth of a comb on the head or thorax, or both, of certain fleas

Word History


New Latin, from cten- + -idium

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Dictionary Entries Near ctenidium

Cite this Entry

“Ctenidium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ctenidium. Accessed 7 Dec. 2023.

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