hydrotheca

noun

hy·​dro·​the·​ca

: a cup-shaped extension of the perisarc in hydroids of the group Leptomedusae that surrounds and protects the hydranths when they are contracted

hydrothecal

¦⸗⸗¦thēkəl

adjective

Word History

Etymology

New Latin, from hydr- + Latin theca sheath, case

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