Gill-opening
GILL-OPENING, noun The aperture of a fish or other animal, by which water is admitted to the gills.
GILL, noun [Low Latin gilla, gillo or gello, a drinking glass, a gill. This word has the same elementary letters as Gr. a pail or bucket, and Eng. gallon, probably from one of the roots in Gl, which signify to hold or contain.]
1. A measure of capacity, containing the fourth part of a pint. It is said to be in some places in England, half a pint.
2. A measure among miners, equal to a pint.
GILL, noun A plant, ground-ivy, of the genus Gleehoma.
1. Malt liquor medicated with ground-ivy.
GILL, noun
1. In ludicrous language, a female; a wanton girl.
Each Jack with his Gill.
2. A fissure in a hill; also, a place between steep banks and a rivulet flowing through it; a brook.