pneumonitis

[Greek pneumōn, lung; see pneumonic + -ITIS.]

An inflammation of the lungs of an acute, localized nature.

Inflammation of lung tissue. See also pneumonia.

• feline p. — see feline pneumonitis.
• hypersensitivity p. — a local type III hypersensitivity reaction resulting from inhalation of antigens, seen in cattle fed moldy hay and the group of diseases in humans that includes farmer's lung and bird-fancier's lung.