aptychus

noun

ap·​ty·​chus
ˈaptə̇kəs
plural aptychi
-ˌkī
: a shelly plate usually of two pieces found in ammonites and regarded as an operculum

Word History

Etymology

New Latin, from a- entry 2 + Greek ptychē fold

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Dictionary Entries Near aptychus

apts

aptychus

APU

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Cite this Entry

“Aptychus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/aptychus. Accessed 25 Nov. 2024.

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