costula

noun

cos·​tu·​la

ˈkäschələ,

-styə-

variants or costule

-schəl,

-styəl

plural costulae

-ˌlē,

-ˌlī

or costules

zoology

: a small ridge (as one of those that make up the sculpture of a mollusk shell)

costulation

ˌ⸗⸗ˈlāshən

noun

plural -s

Word History

Etymology

New Latin costula, from Latin costa rib + New Latin -ula

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