bottlecap

2. A metal crown cap with crimped edges used to seal glass bottles of beer or soda.

The collector sorted his bottlecaps by color and brand.

3. A small decorative or collectible disc shaped like a bottle cap, often used in games or crafts.

The kids glued bottlecaps onto cardboard to make a picture frame.

4. The removable protective cover on a reusable water bottle or thermos.

She lost the bottlecap to her thermos and had to carry it upright.