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

3 April 2025

WHOLE

(noun) an assemblage of parts that is regarded as a single entity; “how big is that part compared to the whole?”; “the team is a unit”


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Coffee Trivia

In 1884, Angelo Moriondo of Turin, Italy, demonstrated the first working example of an espresso machine.

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