TETRAD

four, IV, tetrad, quatern, quaternion, quaternary, quaternity, quartet, quadruplet, foursome, Little Joe

(noun) the cardinal number that is the sum of three and one

Source: WordNet® 3.1


Etymology

Noun

tetrad (plural tetrads)

A group of four things.

Synonyms: foursome, quartet, Thesaurus:quartet

(biology) Two pairs of sister chromatids (a dyad pair) aligned in a certain way and often on the equatorial plane during the meiosis process.

(biology) A group of four haploid and immature pollen grains in tetrahedral fashion produced by meiotic microsporogenesis.

(cartography) A unit of land area of two by two (that is, four) square kilometres.

(chemistry) A tetravalent atom or radical.

(mathematics) A group of four basis vectors for a four-dimensional manifold in differential geometry.

Coordinate terms

• monad · duad, dyad · triad · tetrad · pentad · hexad · heptad · octad · ennead, nonad · decad, decade · hendecad · dodecad, duodecade

Anagrams

• ratted, tarted

Source: Wiktionary


Tet"rad, n. Etym: [L. tetras, -adis, Gr. tétrade.]

1. The number four; a collection of four things; a quaternion.

2. (Chem.)

Definition: A tetravalent or quadrivalent atom or radical; as, carbon is a tetrad.

Source: Webster’s Unabridged Dictionary 1913 Edition



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Word of the Day

2 April 2025

COVERT

(adjective) secret or hidden; not openly practiced or engaged in or shown or avowed; “covert actions by the CIA”; “covert funding for the rebels”


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Coffee Trivia

An article published in Harvard Men’s Health Watch in 2012 shows heavy coffee drinkers live longer. The researchers examined data from 400,000 people and found out that men who drank six or more coffee cups per day had a 10% lower death rate.

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