The slimy, viscous substance secreted in the throat and discharged by coughing, formerly believed to be one of the four cardinal humours of the body. See also humour (3). phlegmatic adj. Calm, unemotional, or cool-headed. [From Latin phlegma phlegm, from Greek phlegma flame, inflammation, or phlegm (thought to be produced by heat), from phlegein to burn]
Subjects: Psychology — Medicine and Health.