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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 ?
In this partnership, Corvus integrates the Identiv 4501 contact and contactless smart card reader board into its recently launched Corvus Tetrad biometric solution, used for border patrol to enhance security through a combined biometric-and-smart card solution.
Corvus Integration is pleased to announce the release of the Corvus Tetrad - a modified version of the Corvus Sleeve biometric solution that utilizes the new Integrated Biometrics Appendix F-certified "Five-O" four-slap fingerprint scanner.
It results from anterior deviation of infundibular septum that cause hypoplasia of sub-pulmonary infundibulum and thus is responsible for tetrad defects e.
The present case report describes the EVC syndrome in a 14-year-old girl, who presented with a tetrad of all the cardinal features and other associated features.
Paulhus and Williams' work has since been expanded into a 'Dark Tetrad,' the fourth condition being narcissism.
Now, following a brief time out from business, Mr Stephenson is back with a new venture, Tetrad, which aims to disrupt the recruitment industry.
For that reason, Tetrad won't be employing anyone with previous recruitment experience - and Neil says his business has the potential to employ 100 and achieve PS10m in revenues in three years.
It is a member of the follicular occlusion tetrad, which also includes hidradenitis suppurativa, acne conglobata, and dissecting cellulitis of the scalp (2).
8 to 3 [micro]m individual size, (5) or packets approximately the size of a red blood cell11; (4) a tetrad packet arrangement (14) (Figure, A), which is a result of the replication occurring in at least 2 planes of growth (5); (5) flattening of the cell walls in areas of contact with adjacent cells (8); and (6) its refractile nature, which can mimic vegetable matter.
These laws of media, which the McLuhans call "the tetrad," can help one to understand and, perhaps, respond constructively to the new medium.
Harris Tweed Hebrides & Tetrad: A UK partnership of two traditional craft companies Harris Tweed Hebrides and Tetrad bring their handcrafted, handwoven products to life in the Nucleus chair.