Lowering the body's normal immune response to invasion by foreign substances

• Can be deliberate (as in lowering the immune response to prevent rejection of a transplanted organ) or incidental (as a side effect of radiotherapy or chemotherapy for cancer)

Wiktionary Word definitions in Wiktionary
n. (context immunology medicine English) The active medical suppression of the immune response.

WordNet Word definitions in WordNet
n. lowering the body's normal immune response to invasion by foreign substances; can be deliberate (as in lowering the immune response to prevent rejection of a transplanted organ) or incidental (as a side effect of radiotherapy or chemotherapy for cancer) ...

Wikipedia Word definitions in Wikipedia
Immunosuppression is a reduction of the activation or efficacy of the immune system . Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to ...