Definition of pin:
(n) :
a small device, made (usually) of drawn-out steel wire with one end sharpened and the other
flattened or rounded into a head, used for
fastening; a small
nail with a
head and a sharp point
"I'm not so good on my pins these days"
(v) :
(often followed by a preposition such as to or on) To fasten or attach (something) with a pin; (chess; usually in the
passive) To cause (a piece) to be in a pin
"...you can't pin that robbery on me!-->"