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petro

[ pe-troh ]
/ ˈpɛ troʊ /
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adjective
of or relating to petroleum or the petroleum industry.
noun
Canadian. the federally owned petroleum industry.
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Origin of petro

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

Other definitions for petro (2 of 3)

petro-1

a combining form meaning “rock,” “stone,” used in the formation of compound words: petrology.
Also petri-; especially before a vowel, petr-.

Origin of petro-

1
<Greek, combining form of pétra rock, pétros a stone

Other definitions for petro (3 of 3)

petro-2

a combining form meaning “petroleum,” “the extraction and export of petroleum,” used in the formation of compound words: petrochemistry; petropower.

Origin of petro-

2
Extracted from petroleum
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

WORDS THAT USE PETRO-

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.

Examples of petro- with the sense “rock”

One example of a term that features petro– in the sense of “rock” is petrology, “the scientific study of rocks.”

The petro– part of the word means “rock,” as we have already seen. The logy part of the word may also look familiar; it is used to name sciences or bodies of knowledge, from Greek logía. Petrology literally translates to “rock science.”

What are some words that use the combining form petro-?

What are some other forms that petro– may be commonly confused with?

Break it down!

A glyph is a pictograph or hieroglyph. With this in mind, what is a petroglyph?

Examples of petro- with the sense “petroleum”

A technical term that features the form petro– as an abbreviation of petroleum is petrodollar, “money, paid in dollars, earned by a country for the exporting of petroleum.”

The petro– part of the word is short for “petroleum”, and the dollar part of the word represents the US dollar. Petrodollar literally means “money [for] petroleum.”

What are some words that use the combining form petro-?

What are some other forms that petro– may be commonly confused with?

Break it down!

There are many different kinds of power wielded by states and nations, such as military power and soft power. With this in mind, what is petropower?

How to use petro in a sentence

British Dictionary definitions for petro

petro-

before a vowel petr-


combining form
indicating stone or rockpetrology
indicating petroleum, its products, etcpetrochemical
of or relating to a petroleum-producing countrypetrostate

Word Origin for petro-

from Greek petra rock or petros stone
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

Medical definitions for petro

petro-

pref.
Rock; stone; stone-like hardness:petrous.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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