petrology petrologically • petrol pump · · · Info · Definitions · Synonyms · Characters · · petrology · · Text Latin · · Script 9 · · Length 4 · · Syllables Definitions · · · (noun) the branch of geology that studies rocks: their origin and formation and mineral composition and classification. Synonyms: lithology. · · Noun Definition 1 Synonyms · · · lithology · · Synonym 1 Characters · · e latin small letter e U+0065 g latin small letter g U+0067 l latin small letter l U+006C o latin small letter o U+006F p latin small letter p U+0070 r latin small letter r U+0072 t latin small letter t U+0074 y latin small letter y U+0079