Main Entry: pe·trol·o·gy

Pronunciation: \pə-ˈträ-lə-jē, pe-\

Function: noun

Etymology: International Scientific Vocabulary

Date: 1811

: a science that deals with the origin, history, occurrence, structure, chemical composition, and classification of rocks

— pet·ro·log·ic \ˌpe-trə-ˈlä-jik\ or pet·ro·log·i·cal \-ji-kəl\ adjective

— pet·ro·log·i·cal·ly \-ji-k(ə-)lē\ adverb

— pe·trol·o·gist \pə-ˈträ-lə-jist, pe-\ noun