: a thin, pointed piece of stiff wire with a rounded head at one end that is used especially for fastening pieces of cloth
: a thin, pointed piece of stiff wire with a decoration at one end
: a small usually circular object that has writing and often a picture on it and that has a pin on the back so that it can be fastened to clothing, bags, etc.
: to fasten or attach (something) with a pin
: to prevent or stop (someone or something) from moving by holding or pressing firmly against something
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