collar

In clothing, a collar is the part of a shirt, dress, coat or blouse that fastens around or frames the neck. Among clothing construction professionals, a collar is differentiated from other necklines such as revers and lapels, by being made from a separate piece of fabric, rather than a folded or cut part of the same piece of fabric used for the main body of the garment.
A collar may be permanently attached to the main body of the garment (e.g. by stitching) or detachable.

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