# mesotheca

> English word · Noun

## Definitions
1. The middle layer of the gonophore in the Hydrozoa.
2. A membranous structure that encloses the developing eggs within the oviduct of a female arthropod.

## Etymology
From meso- + theca.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/mesotheca