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petro

1 American  
[pe-troh] / ˈpɛ troʊ /

adjective

  1. of or relating to petroleum or the petroleum industry.


noun

  1. Canadian. the federally owned petroleum industry.

petro- 2 American  
  1. a combining form meaning “rock,” “stone,” used in the formation of compound words.

    petrology.


petro- 3 American  
  1. a combining form meaning “petroleum,” “the extraction and export of petroleum,” used in the formation of compound words.

    petrochemistry; petropower.


petro- British  

combining form

  1. indicating stone or rock

    petrology

  2. indicating petroleum, its products, etc

    petrochemical

  3. of or relating to a petroleum-producing country

    petrostate

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does petro- mean? Petro- is a combining form used like a prefix that has two distinct senses.The first of these senses is “rock” or "stone," and this form of petro- is occasionally used in a variety of scientific and technical terms. Petro- comes from Greek pétra, meaning “rock.” Two Latin translations of pétra are lapis and saxum, both meaning “stone,” which are the roots of terms such as lapis lazuli and saxifrage, respectively. To learn more, check out our entries for both words.The second of these senses is “petroleum,” and this form of petro- is occasionally used in a variety of technical terms. Petro- is an abbreviation of the word petroleum, from the Medieval Latin word for "rock oil; the -oleum element means "oil" in Latin. Find out more about the word petroleum at our entry for the word.What are variants of petro- with the sense “rock”?Petri- is a variant of petro-, which exchanges its -o- for an -i- when combined with words or word elements beginning with certain consonants. Another variant for petro- in this sense is petr-, which loses its -o- combined with words or word elements beginning with vowels. Want to know more? Read our Words That Use articles for petri- and petr-.Not every word that begins with the exact letters petro- or petr-, such as petronel or petrel, is necessarily using the combining form petro- to denote “rock” or "petroleum.” Learn why petrel is the name of a seabird at our entry for the word.

Etymology

Origin of petro1

First recorded in 1970–75; independent use of petro- 2

Origin of petro-2

< Greek, combining form of pétra rock, pétros a stone

Origin of petro-3

Extracted from petroleum

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

President Gustavo Petro's left-wing coalition was on track to be the largest bloc in Colombia's next Congress on Monday, after a better-than-expected showing in legislative elections.

From Barron's

Whoever replaces Petro in August will confront a splintered Congress that will force any incoming administration to build alliances to pass laws.

From Barron's

Petro, a former guerrilla and Colombia's first leftist president, is barred by the constitution from running again.

From Barron's

Colombians started voting Sunday in legislative elections that will shape the final months of left-wing President Gustavo Petro's term and test whether the once-powerful right wing is poised for a political comeback.

From Barron's

Petro, a former guerrilla, became Colombia's first-ever leftist leader in 2022.

From Barron's