[noun] a band that fits around the neck and is usually folded over Synonyms:neckband
[noun] a band of leather or rope that is placed around an animal's neck as a harness or to identify it
[noun] necklace that fits tightly around a woman's neck Synonyms:choker, dog neckband
[noun] a figurative restraint; "asked for a collar on program trading in the stock market"; "kept a tight leash on his emotions"; "he's always gotten a long leash" Synonyms:leash