Abdominal cavity
The abdominal cavity was the largest body cavity in Humans containing several organs; Trills possessed more than one such cavity.

In 2374, Jadzia Dax suffered a puncture of the right abdominal cavity and injury to the Dax symbiont when Sisko's attack ship came under fire from the Jem'Hadar. Doctor Julian Bashir was later able to heal her internal injuries. ()

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Anatomy