Definition of asthma
: a chronic lung disorder that is marked by recurring episodes of airway obstruction (as from bronchospasm) manifested by labored breathing accompanied especially by wheezing and coughing and by a sense of constriction in the chest, and that is triggered by hyperreactivity to various stimuli (such as allergens or rapid change in air temperature)
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Merriam-Webster unabridged
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Time Traveler for asthma
The first known use of asthma was in the 14th century
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