Ratchet wheel and Sprocket wheel

Ratchet wheel noun - Toothed wheel held in place by a pawl or detent and turned by a lever.

Sprocket wheel and ratchet wheel are semantically related. in wheel with teeth topic. In some cases you can use "Sprocket wheel" instead a noun phrase "Ratchet wheel".

Sprocket wheel noun - Thin wheel with teeth that engage with a chain.

Ratchet wheel and sprocket wheel are semantically related. Sometimes you can replace phrase "Ratchet wheel" with "Sprocket wheel", this phrases are similar.