collar · noun C /ˈkɒl.ər/Full view
collar (PART OF CLOTHES)
B1 the part of a shirt, coat, etc. that is usually folded over and goes round your neck
Dictionary examples:

a shirt collar

a fur collar

Learner example:

It's a new, fashionable one with [a] high collar and short sleeves. (Preliminary English Test; B1; Thai)

collar (ON AN ANIMAL)
B2 a strap made of leather or other strong material which is put around the neck of an animal, especially a dog or cat
Dictionary examples:

a dog collar

I grabbed the dog by its collar and dragged it out of the room.

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