Pronunciation: im′yū-nō-dē-fish′en-sē, i-myū′
1. A condition resulting from a defective immune mechanism; may be primary (due to a defect in the immune mechanism itself) or secondary (dependent on another disease process), specific (due to a defect in either the B-lymphocyte or the T-lymphocyte system, or both) or nonspecific (due to a defect in one or another component of the nonspecific immune mechanism: the complement, properdin, or phagocytic system).
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