tetrad


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tet·rad

 (tĕt′răd′)
n.
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.

tetrad

(ˈtɛtræd)
n
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]

tet•rad

(ˈtɛ træd)

n.
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]

Tetrad

 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"
Translations

tet·rad

n. tétrada, grupo de cuatro elementos similares.
References in periodicals archive ?
Though the small nails and triangular lunulae may be what brings the patient to the dermatologist's office, a careful exam and one radiograph can pick up a tetrad of anomalies, Dr.
The so-called Blood Moon phenomenon, which is mentioned in the aforequoted Biblical verses (Joel 2:31; Acts 2:20; and Revelation 6:12) is referred to as Tetrad. This term tetrad was coined by NASA (National Aeronautics and Space Administration) to describe a series of four blood moon back-to-back red lunar eclipses (total eclipses).
John Hagee and Mark Biltz first introduced the 'Blood Moon Prophecy' in 2014, claiming that the ongoing 'tetrad' - four consecutive lunary eclipses, indicates the end of Earth as described in the Bible in Acts 2:20 and Revelation 6:12.
In 2014 and 2015, the world witnessed four consecutive total eclipses of the moon, known as a tetrad.
Nevertheless, some irregular shapes in the normalized REE curves can be observed owing to the lanthanide tetrad effect (LTE) (Censi et al., 2007; Rezaei Azizi et al., 2017; Abedini et al., 2018b,c).
In general, the REE patterns of the studied bulk rock pegmatite display tetrad effect and low total REE abundances, strong positive Eu anomalies, weak negative Ce anomalies and relative enrichment in heavy REE.
It states that a tetrad (four consecutive lunar eclipses) supposedly began on April, 4 2014, followed by blood moons on October 8, 2014, April 4, 2015 and September 28, 2015, with six full moons in between.
According tothe Mirror, the claims were originally made famous by Christian ministers John Hagee and Mark Biltz who said the ongoing "tetrad" - four consecutive lunar eclipses which began in April 2014 with six full moons in between - is the indicator of the end of earth as described in the Bible in Acts 2:20 and Revelation 6:12.
According toMirror Online, the hypothesis was originally made famous by Christian ministers John Hagee and Mark Biltz who said the ongoing "tetrad" -- four consecutive lunar eclipses which began in April 2014 with six full moons in between -- is the indicator of the end of earth as described in the Bible in Acts 2:20 and Revelation 6:12.
Recruitment specialist, Tetrad, has appointed Recruitment Employment Confederation (REC) North East director Kelly Adamson to its board as chief executive officer.
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.
The most dominant variable in the underlying gravity is the tetrad field [e.sub.a]([x.sup.[lambda]]).