tu·ber·cu·lo·sis (t-bûr′kyə-lōsĭs, ty-)
n. Abbr. TB
1. An infectious disease of humans and animals caused by the tubercle bacillus and characterized by the formation of tubercles on the lungs and other tissues of the body, often developing long after the initial infection.
2. Tuberculosis of the lungs, characterized by the coughing up of mucus and sputum, fever, weight loss, and chest pain.
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