1. the breathing organs of fish and other aquatic animals that extract oxygen from water
2. the thin plates on the underside of a mushroom cap
Usage: botany

Examples

• The fish opened and closed its gills to breathe underwater.
• Sharks have five to seven gill slits on each side of their head.
• The salmon’s gills were bright red from the flowing blood.
• She examined the mushroom’s white gills with a magnifying glass.
• The mycologist identified the species by studying its gills.
• Water flows over the gills and oxygen is absorbed into the bloodstream.
• The gills of the portobello mushroom were dark brown and well-developed.