# cassiosome

> English word · Noun

## Definitions
1. A stinging-cell structure, composed of a layer of mainly nematocytes surrounding a core of dinoflagellates, amoebocytes and mesoglea, expelled within mucus by Rhizostomeae jellyfish to sting (and in some cases kill) prey in the surrounding water.

## Etymology
From Cassio(pea) (a genus of jellyfish) + -some, referring to a genus containing some of the jellyfish found to produce them. Coined 2020 by Cheryl L. Ames, et al., in a paper published in Communications Biology (see quotations below).

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