pin·tle 
(pĭntl)
(pĭntl)n.
1. A pin or a bolt on which another part pivots.
2. Nautical The pin on which a rudder turns.
3. The pin on which a gun carriage revolves.
4. A hook or a bolt on the rear of a towing vehicle for attaching a gun or trailer.
[Middle English pintel, penis, from Old English.]