1
: stone : rock
petrology
2
: petroleum
petrodollar

Word History

Etymology

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

Dictionary Entries Near petro-

Cite this Entry

“Petro-.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/petro-. Accessed 7 Dec. 2022.

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