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petro-

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

    petrology.


petro- 2 American  
  1. a combining form meaning “petroleum,” “the extraction and export of petroleum,” used in the formation of compound words.

    petrochemistry; petropower.


petro 3 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- 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 petro-1

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

Origin of petro-1

Extracted from petroleum

Origin of petro1

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

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.

Pleased with his offer of co-operation, the government of Colombian President Gustavo Petro named Mancuso a "promoter of peace", saying he would act as a mediator between the administration and illegal armed groups still active in the country.

From BBC

"We'll see the results of that meeting," Petro said during a televised meeting with his ministers.

From Barron's

Any real plan for reviving Venezuela’s oil industry has to reckon with the political legacy of the country’s long, turbulent history with its petro riches.

From The Wall Street Journal

Colombia's President Gustavo Petro on Friday urged Venezuela to jointly fight drug-traffickers operating across the two countries' border, after the United States threatened further armed action in the region.

From Barron's

But on Thursday, Petro's tone suggested relations had not significantly improved.

From BBC