Search Result for "opportunistic infection":
Wordnet 3.0

NOUN (1)

1. any infection caused by a microorganism that does not normally cause disease in humans; occurs in persons with abnormally functioning immune systems (as AIDS patients or transplant patients receiving immunosuppressive drugs); 



WordNet (r) 3.0 (2006):

opportunistic infection
    n 1: any infection caused by a microorganism that does not
         normally cause disease in humans; occurs in persons with
         abnormally functioning immune systems (as AIDS patients or
         transplant patients receiving immunosuppressive drugs)