Definition of petro-

1 : stone : rock petrology
2 : petroleum petrodollar

History and Etymology for petro-

borrowed from Greek, combining form from pétrā "rocky cliff, cave, detached mass of rock, stone" and pétros "boulder, stone," probably of pre-Greek substratal origin

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Cite this Entry

“Petro-.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/petro-. Accessed 18 Sep. 2020.

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