WordNet sense 1 (the stitching that forms the rim of a shoe or boot):

shoe collar

WordNet sense 2 (a band that fits around the neck and is usually folded over):

neckband

WordNet sense 3 (necklace that fits tightly around a woman's neck):

choker, dog collar

WordNet sense 4 (take into custody):

apprehend, arrest, cop, nab, nail, pick up

WordNet sense 5 (a figurative restraint):

leash

WordNet sense 6 (the act of apprehending (especially apprehending a criminal)):

apprehension, catch, pinch, taking into custody