PYOPNEUMOTHORAX
Py`op*neu`mo*tho"rax, n. Etym: [Gr. pneumothorax.] (Med.)

Defn: Accumulation of air, or other gas, and of pus, in the pleural cavity.

PYOT
Py"ot, n. (Zoöl.)

Defn: The magpie. See Piet.

PYOXANTHOSE
Py`o*xan"those, n. Etym: [Gr. (Physiol. (Chem.)

Defn: A greenish yellow crystalline coloring matter found with pyocyanin in pus.

PYRACANTH
Pyr"a*canth, n. Etym: [Gr. (Bot.)

Defn: The evergreen thorn (Cratægus Pyracantha), a shrub native of
Europe.

PYRAL
Py"ral, a.

Defn: Of or pertaining to a pyre. [R.]