Hydrocarbon and Naphthalene

Hydrocarbon noun - An organic compound containing only carbon and hydrogen.

Naphthalene and hydrocarbon are semantically related. In some cases you can replace term "Naphthalene" with "Hydrocarbon", this nouns are similar.

Naphthalene noun - A white crystalline strong-smelling hydrocarbon made from coal tar or petroleum and used in organic synthesis and as a fumigant in mothballs.

Hydrocarbon and naphthalene are semantically related. You can use "Hydrocarbon" instead a noun "Naphthalene".