cough

cough   (kôf, kŏf)    v.   coughed, cough·ing, coughs v.   intr. To expel air from the lungs suddenly and noisily, often to keep the respiratory passages free of irritating material. To make a noise similar to noisy expulsion of air from the lungs: The engine coughed and died. v.   tr. To expel by coughing: coughed up phlegm. n.   The act of coughing. An illness marked by frequent coughing. Phrasal Verb(s): cough up Slang To hand over or relinquish (money or another possession), often reluctantly. To confess or disclose: When he saw that the police might arrest him, he coughed up the details of what he had seen. [Middle English coughen, ultimately of imitative origin.]

cough 

Main Entry: ¹cough
Pronunciation: 'kof
Function: intransitive verb
: to expel air from the lungs suddenly with an explosive noise usually in aseries of efforts cough transitive senses
: to expel by coughing —often used with up <cough up mucus>

cough (kôf)
v. coughed, cough·ing, coughs
To expel air from the lungs suddenly and noisily, often to keep the respiratory passages free of irritating material. n.

1. The act of coughing.

2. An illness marked by frequent coughing.

cough

an expulsive reflex initiated when the respiratory tract is irritated by infection, noxious fumes, dust, or other types of foreign bodies. The reflex results in a sudden expulsion of air from the lungs that carries with it excessive secretions or foreign material from the respiratory tract. Cough is beneficial; pneumonia frequently results when an effective cough reflex is lost as a result of chest injury, disease, or oversedation. Repeated and severe coughing, however, is physically exhausting and interferes with rest. Under these circumstances drugs may be used to suppress the reflex.

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