tet·​ra | \ ˈte-trə How to pronounce tetra (audio) \

Definition of tetra

 (Entry 1 of 2)

: any of numerous small often brightly colored South American characin fishes often bred in tropical aquariums
variants: or tetr-

Definition of tetra- (Entry 2 of 2)

1 : four : having four : having four parts tetravalent
2 : containing four atoms or groups (of a specified kind) tetrachloride

Examples of tetra in a Sentence

Recent Examples on the Web: Noun Because cavefish have evolved to live in an oxygen deficient environment, researchers weren't surprised to find that embryonic specimen exhibited more gene markers for hypoxia in comparison to the Mexican tetra. Daisy Hernandez, Popular Mechanics, "This Eyeless Fish Could Help Find a Cure For a Human Disease," 11 June 2020 Jio’s milk tetra packs were puffed and dirty like someone picked them up from the mud and put them directly in the bag. Ananya Bhattacharya, Quartz India, "JioMart has started off on a rotten note. But that won’t upset its applecart," 3 June 2020 Like Mendez, who was born with an extremely rare condition called tetra-amelia syndrome, Perrino faces a multitude of challenges every day. BostonGlobe.com, "That is until he tuned into the ESPY Awards in July and saw Rob Mendez, a football coach from California. Mendez, who does not have arms, legs, or inhibitions, took the stage and delivered an impassioned acceptance speech in receiving the Jimmy V Award for Perseverance.," 24 Sep. 2019 Rob Mendez was born with tetra-amelia syndrome Nothing has ever gotten in the way of Rob Mendez and his dreams. Lindsay Kimble, PEOPLE.com, "Rob Mendez, Football Coach with No Limbs, Aims to Inspire in New Film: 'Focus on What You Can Do'," 28 Aug. 2019 Mendez, as introduced in a 2016 story by this news organization, was born with tetra-amelia syndrome. Gary Peterson, The Mercury News, "Armless, legless South Bay football coach honored at ESPYS has a message for you," 11 July 2019 Mendez was born with the rare disorder tetra-amelia syndrome and was unable to play football growing up despite his passion for the sport. Alaa Abdeldaiem, SI.com, "High School Football Coach Born Without Arms, Legs Wins ESPN's Jimmy V Award," 19 June 2019 Mendez was born with the rare tetra-amelia syndrome, which caused him to be born without arms or legs. Jon Becker, The Mercury News, "South Bay coach born without arms, legs wins ESPN’s Jimmy V Award," 18 June 2019 The queue doubles as an aquarium, and riders follow a twisting route through tanks filled with angelfish, tetras, seahorses, an octopus and seven varieties of rays. Lauren Weber, WSJ, "Roller-Coaster Designer on the Ups and Downs of His Work," 14 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tetra.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tetra


1931, in the meaning defined above

History and Etymology for tetra


by shortening from New Latin Tetragonopterus, former genus name, from Late Latin tetragonum quadrangle + Greek pteron wing — more at tetragonal, feather

Combining form

New Latin, from Greek; akin to Greek tettares four — more at four

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Time Traveler for tetra

Time Traveler

The first known use of tetra was in 1931

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Cite this Entry

“Tetra.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tetra. Accessed 20 Jan. 2021.

More from Merriam-Webster on tetra

Britannica.com: Encyclopedia article about tetra

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