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aptychus

noun
ap·ty·chus | \ ˈaptə̇kəs \
plural aptychi\-ˌkī \

Definition of aptychus 

: a shelly plate usually of two pieces found in ammonites and regarded as an operculum

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History and Etymology for aptychus

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

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Dictionary Entries near aptychus

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aptitude test

apts

aptychus

APU

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Apulian

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occurring twice a year or every two years

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