Clack (verb)

1. Make a loud, sharp noise, typically by striking two hard surfaces together.
2. Make a sharp, repetitive noise, typically by striking two hard surfaces together repeatedly.

Origin:

From the middle english clakken, from the old english clæccan ("to make a loud, sharp noise"). the term clack was first used in the 14th century to refer to the sound made when two hard surfaces are struck together.

Examples:

1. The old gate clacked in the wind.
2. The castanets clacked together.
3. He clacked his heels together.
4. The machine clacked noisily.
5. The train wheels clacked on the tracks.