Chemical weapon and Pepper spray

Chemical weapon noun - Chemical substances that can be delivered using munitions and dispersal devices to cause death or severe harm to people and animals and plants.

Pepper spray and chemical weapon are semantically related. In some cases you can replace phrase "Pepper spray" with "Chemical weapon", this phrases are similar.

Pepper spray noun - A nonlethal aerosol spray made with the pepper derivative oleoresin capiscum; used to cause temporary blindness and incapacitate an attacker; also used as a bear deterrent.

Chemical weapon and pepper spray are semantically related. You can use "Chemical weapon" instead a noun phrase "Pepper spray".