phonolitePronunciation: /ˈfəʊnəlʌɪt/Definition of phonolite noun [mass noun] Geology a fine-grained volcanic igneous rock composed of alkali feldspars and nepheline. Origin: early 19th century: from phono- 'relating to sound' (because of its resonance when struck) + -ite1phonolite in other Oxford dictionaries Definition of phonolite in the US English dictionary
