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A fish breathes by swallowing water and passing it through gill slits on each side of its head. Blood-filled filaments on the gills extract oxygen from the water as it flows through.
1. Zoology The respiratory organ of most aquatic animals that obtain oxygen from water, consisting of a filamentous structure of vascular membranes across which dissolved gases are exchanged.
a. often gills The wattle of a bird.
b. gills Informal The area around the chin and neck.
3. Botany One of the thin, platelike structures on the underside of the cap of a mushroom or similar fungus.
v. gilled, gill·ing, gills
1. To catch (fish) in a gill net.
2. To gut or clean (fish).
To become entangled in a gill net. Used of fish.
to the gills Informal
As full as possible; completely.
[Middle English gile, of Scandinavian origin.]
n. Abbr. gi or gi.
1. A unit of volume or capacity in the US Customary System, used in liquid measure, equal to 1/4 of a pint or four ounces (118 milliliters).
2. A unit of volume or capacity, used in dry and liquid measure, equal to 1/4 of a British Imperial pint (142 milliliters).
[Middle English gille, from Old French, wine measure, from Late Latin gillō, vessel for cooling liquids.]
n. Chiefly British
1. A ravine.
2. A narrow stream.
[Middle English gille, from Old Norse gil.]
gill 4also jill or Gill (jĭl)
A girl, often one's sweetheart.
[Middle English gille, from Gille, a woman's name.]
1. (Zoology) (sometimes singular) the wattle of birds such as domestic fowl
2. green around the gills green about the gills informal looking or feeling nauseated