Dictionary
op•por•tun•is•tic
Pronunciation: (op"ur-tOO-nis'tik, -tyOO-), [key]—
adj.
1. adhering to a policy of opportunism; practicing opportunism.
2. Pathol.
a. (of a microorganism) causing disease only under certain conditions, as when a person's immune system is impaired.
b. (of a disease or infection) caused by such an organism:
Pneumocystis pneumonia is an opportunistic disease that often strikes victims of AIDS. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.