What does tetra- mean? Tetra- is a combining form used like a prefix meaning “four.” It is used in a great many scientific and other technical terms. In chemistry, tetra- is specifically used to indicate four atoms or four groups of atoms in compounds, e.g., tetrachloride. Tetra- ultimately comes from the Greek téttares, meaning “four.” The name of the classic video game Tetris is based in part on this Greek root. Find out the rest of the story of how Tetris got its name here. The Latin word for “four” is quattor, source of the combining forms quadr-, quadra-, quadri-, and quadru-. Learn about their specific applications in our Words That Use articles for the forms. What are variants of tetra-?When combined with words or word elements that begin with a vowel, tetra- becomes tetr-, as in tetracid.
1930–35; shortening of New Latin Tetragonopterus former genus name. See tetragon, -o-, -pterous
< Greek, combining form of téttara, neuter of téttares four
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Other exhibits displayed early cordless phones, Tetra Pak’s shelf-stable milk containers and pay-at-the-pump gas-station transactions.
From The Wall Street Journal • May 16, 2026
The New York-based company’s Tetra Paks—four-sided paperboard cartons emblazoned with palm trees—lead the coconut water pack, dominating the U.S. market with a 44% market share.
From Barron's • Nov. 13, 2025
The EY audit also flagged issues with several other contractors, including Tetra Tech and Arcadis, according to draft records obtained from EY by Larson’s attorneys and submitted as evidence at trial.
From Los Angeles Times • Sep. 8, 2025
The company overseeing the project is Tetra Tech, a publicly traded consulting and engineering firm based in the U.S., and a Vietnamese construction firm has been tasked with the excavation work.
From Salon • Mar. 19, 2025
In Vienna I had become acquainted with a Hungarian nobleman, whose father owned large estates at the foot of the Tetra mountains.
From Problematic Characters A Novel by Spielhagen, Friedrich
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
