n, pl  -co*ses   :  an infectious disease of birds caused by a bacterium of the genus Chlamydia (C. psittaci), marked by diarrhea and wasting, and transmissible to humans in whom it usu. occurs as an atypical pneumonia accompanied by high fever - called also parrot fever  - compare ORNITHOSIS  psit*ta*co*tic adj 
 
 
 
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