[pe-truh-grad; Russian pyi-truh-graht] /ˈpɛ trəˌgræd; Russian pyɪ trʌˈgrɑt/ noun 1. former name (1914–24) of (def 2). /ˈpɛtrəʊˌɡræd; Russian pɪtraˈɡrat/ noun 1. a former name (1914–24) of Saint Petersburg
[pe-truh-gram] /ˈpɛ trəˌgræm/ noun 1. a drawing or painting on rock, especially one made by a member of a prehistoric people.
[pe-truh-graf, -grahf] /ˈpɛ trəˌgræf, -ˌgrɑf/ noun 1. . noun a rock inscription or painting
[pi-trog-ruh-fee] /pɪˈtrɒg rə fi/ noun 1. the branch of petrology dealing with the description and classification of rocks, especially by microscopic examination. /pɛˈtrɒɡrəfɪ/ noun 1. the branch of petrology concerned with the description and classification of rocks petrog petrography (pə-trŏg’rə-fē) The description and classification of rocks, especially by means of microscopic analysis.