Mycobacterium avi·um complex noun \-ˈā-vē-əm-, -ˈä-\ : two
bacteria of the genus Mycobacterium (M. avium and M.
intracellulare) that account for most mycobacterial infections
in humans other than tuberculosis, that usually affect the lungs
but may involve the lymph nodes, bones, joints, and skin, and
that may cause disseminated disease in immunosuppressed
conditions (as AIDS)—abbreviation MAC Seen & Heard What made you
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