spur

A short spike or spiked wheel that attaches to the heel of a rider’s boot and is used to urge a horse forward.

An incentive.

A spurlike attachment or projection, as.

A spinelike process on the leg of some birds.

A climbing iron; a crampon.

A gaff attached to the leg of a gamecock.

A short or stunted branch of a tree.

A bony outgrowth or protuberance.

A lateral ridge projecting from a mountain or mountain range.

An oblique reinforcing prop or stay of timber or masonry.