naphtheneEnglishOxford New American Dictionarynaphthene /ˈnafˌTHēn, , ˈnæfˌθin , ˈnapˌTHēn, ˈnæpˌθin / ▸ noun Chemistry any of a group of cyclic aliphatic hydrocarbons (e.g. cyclohexane) obtained from petroleum. – DERIVATIVES naphthenic /napˈTHenik, , næpˈθɛnɪk, napˈTHēnik, , næpˈθinɪk, nafˈTHenik, , næfˈθɛnɪk, nafˈTHēnik, næfˈθinɪk/ adjective