Cobalt and Ether

Cobalt noun - A hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutrition.

Ether and cobalt are semantically related. In some cases you can use "Ether" instead an adjective "Cobalt".

Ether noun - Any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom.

Cobalt and ether are semantically related. Sometimes you can use "Cobalt" instead an adjective "Ether".