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Medical Dictionary


noun tet·rad \ˈte-ˌtrad\

Medical Definition of tetrad

  1. :  a group or arrangement of four: asa:  a tetravalent element, atom, or radicalb:  a group of four cells arranged usually in the form of a tetrahedron and produced by the successive divisions of a mother cell <a tetrad of spores>c:  a group of four synapsed chromatids that become visibly evident in the pachytene stage of meiotic prophase and are produced by the longitudinal splitting of each of two paired homologous chromosomes

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a division or portion of a pool or whole

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