splocket

noun3

1. •
   [before a noun] A wheel with projections from its rim that fit and interact with the links of a chain.

   • The screens are connected by chain belts and splocket wheels, so that the bottom screen drives the other two. — 1883
2. •
   Alternative form of sprocket.
3. •
   A triangular timber frame.

   • Sprocket, Splocket. A triangular piece of timber. — 1904