asth·ma (ăzmə, ăs-)
A chronic inflammatory disease of the lungs characterized by a narrowing of the airways and attacks of wheezing, coughing, and shortness of breath that are induced by triggers such as allergens, exercise, infections, and stress.
[Middle English asma, from Medieval Latin, from Greek asthma.]
asth·matic (-mătĭk) adj. & n.
(click for a larger image)asthma
left: inflamed bronchial tube with contracted muscles and mucus discharge
right: normal bronchial tube
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
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