phlegm Definition

phlegm
noun

1. A thick yellowish substance produced by the mucous membrane that lines the air passages, brought up by coughing.
2. Calmness or impassiveness; stolidity or sluggishness of temperament.
3. physiol., historical
One of the four humours (see humour noun 6) or bodily fluids, ie the humour characterized as cold and moist.

Derivative: phlegmy
adj

Etymology: 14c as fleume: French, from Greek phlegma flame, heat, phlegm (thought to be the result of heat) or inflammation.