runt(redirected from runtiness)
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A stunted animal, occurring most frequently in species that give birth to large litters.
small, stunted, weak; an undersized offspring. See also intrauterine growth retardation.
disease produced by immunologically competent cells in a foreign host that is unable to reject them, resulting in gross retardation of host development and in death. Classically observed in neonatal mice given bone marrow or leukocytes from an adult, genetically different strain of mice; a form of graft versus host disease.