Diphenyl is a term used to describe a chemical compound consisting of two connected phenyl groups. This chemical compound is also known by other names such as biphenyl, phenylbenzene, and 1,1-biphenyl. Biphenyl is a more popular synonym for diphenyl and is widely used in the chemical industry. Other synonyms for diphenyl include diphen, lemonine, and diphenylethane. Diphenyl is commonly used in the production of dyes, resins, plastics, and as a heat transfer agent. Knowing the various synonyms for diphenyl can be helpful in understanding its use in different industries and applications.