noun, slang ·Moderate ·College level

Definitions

Noun

1. 1
   A half-cylindrical or half-conical shaped opening or void in a lapped edge or seam, usually caused by wrinkling or shifting of ply sheets during installation.
2. 2
   A wide incision made to drain fluid from under the fingernail.
3. 3
   A horizontal incision on the breast aligned with the nipples made to drain or excise the breast fat as a form of top surgery.
4. 4
   A chronically open mouth. colloquial

Etymology

From fish + mouth.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.