<unk>  is expectorated matter especially from the air passages in diseases of the lungs, bronchi, or upper respiratory tract. It is matter that is coughed up from the respiratory tract, such as mucus or phlegm, mixed with saliva and then expectorated from the mouth.
Sputum
Exudate
Blood
Pleural effusion laboratory findings
Bacterial pneumonia physical examination
Lung abscess laboratory findings
Serum
Pleural effusion physical examination