pl. sputa [L. sputum, spit, spittle]
Mucus expelled from the lung by coughing. It may contain a variety of materials from the respiratory tract, including in some instances cellular debris, mucus, blood, pus, caseous material, and/or microorganisms.
A wide variety of illnesses, including typical and atypical pneumonias, tuberculosis, cancers of the lungs or bronchi, reactive airway disease, and occupational diseases of the lungs can be diagnosed with gram staining or culturing of sputum, cytological examination of sputum, or the use of special stains and microscopic techniques.
The color or thickness of sputum is not a reliable diagnosis of an illness.
There's more to see -- the rest of this topic is available only to subscribers.