1. (noun) any of the radiating leaflike spore-producing structures on the underside of the cap of a mushroom or similar fungus

• gill

1. (noun) any of the radiating leaflike spore-producing structures on the underside of the cap of a mushroom or similar fungus

• plant organ

2. (noun) a thin membrane that is one of the calcified layers that form bones

• membrane
• tissue layer

3. (noun) thin plate

• plate