| 1. | the respiratory organ of aquatic animals, as fish, that breathe oxygen dissolved in water. |
| 2. | Also called lamella. one of the radiating vertical plates on the underside of the cap of an agaric mushroom. |
| 3. | ground ivy. |
| 4. | to gut or clean (fish). |
| 5. | to catch (fish) by the gills in a gill net. |
| 6. | green or white around the gills, somewhat pale, as from being sickly, nervous, or frightened: When he heard how much the bill was, he looked a little green around the gills. |
| 7. | to the gills, Informal. fully; completely; totally: After that big meal we were all stuffed to the gills. |

gill 2 (jĭl) n. Abbr. gi or gi.
[Middle English gille, from Old French, wine measure, from Late Latin gillō, vessel for cooling liquids.] |
gill
in biology, type of respiratory organ found in many aquatic animals, including a number of worms, nearly all mollusks and crustaceans, some insect larvae, all fishes, and a few amphibians. The gill consists of branched or feathery tissue richly supplied with blood vessels, especially near the gill surface, facilitating the exchange of oxygen and carbon dioxide with the surrounding water. The gills may be enclosed in cavities, through which the water is often forcibly pumped, or they may project from the body into the water.
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