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Related to tetrad: Tetrad analysis


1. A group or set of four.
2. A tetravalent atom, radical, or element.
3. Biology
a. A four-part structure that forms during the prophase of meiosis and consists of two homologous chromosomes, each composed of two sister chromatids.
b. A group of four haploid cells, such as spores, formed by meiotic division of one mother cell.

[Greek tetras, tetrad-; see kwetwer- in Indo-European roots.]

te·trad′ic adj.


1. (Mathematics) a group or series of four
2. (Mathematics) the number four
3. (Biology) botany a group of four cells formed by meiosis from one diploid cell
4. (Genetics) genetics a four-stranded structure, formed during the pachytene stage of meiosis, consisting of paired homologous chromosomes that have each divided into two chromatids
5. (Chemistry) chem an element, atom, group, or ion with a valency of four
6. (Environmental Science) ecology a square of 2 × 2 km used in distribution mapping
[C17: from Greek tetras, from tettares four]


(ˈtɛ træd)

1. a group of four.
2. the number four.
3. Biol. a group of four chromatids formed by synapsis at the beginning of meiosis.
[1645–55; < Greek tetrad-, s. of tetrás group of four]


 a group of four; four things regarded together as a single object or thought.
Example: Great Tetrad of senior wranglers, 1898.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.tetrad - the cardinal number that is the sum of three and onetetrad - the cardinal number that is the sum of three and one
digit, figure - one of the elements that collectively form a system of numeration; "0 and 1 are digits"


n. tétrada, grupo de cuatro elementos similares.
References in periodicals archive ?
Proposals shall be mailed or delivered to: Tetrad Property Group,2021 Transformation Drive, Suite 1100,Lincoln, NE 68508.
The tetrad is said be some to signal the End of Days, while others believe it signifies a significant religious event.
It will be the fourth of four total lunar eclipses in a two year period, which is known as a Lunar Tetrad - four total lunar eclipses six months apart.
RBZ governor, John Mangudya, acknowledged that Metbank, Afrasia Bank Zimbabwe and Tetrad Investment Bank continued to experience liquidity and solvency challenges.
The cute and chunky Harris Tweed Pumpkin Stools from Tetrad are perfect for keeping your feet up off the floor and higher up in the heat.
After meiosis II numerous tetrads of microspores appear, tetrad shape is tetrahedral and the wall formation taking place after each stage of meiosis.
The so-called tetrad is unusual because the full eclipses are visible in all or parts of the United States, according to retired NASA astrophysicist Fred Espenak.
MENTOR, OH -- Libra Industries has acquired fellow EMS firm Tetrad Electronics for an undisclosed amount.
Horizon Capital, a consortium of Russian investors, has recently completed the takeover of Tetrad, a Zimbabwean financial institution.
According to Tetrad every media can be analyzed based on four questions: 1) what does this media reinforce in a culture?