phlegm

physiological humor

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Last updated

July 23, 2026

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In ancient Greek medicine, phlegm was considered one of the four humors that controlled personality. Paired with water, phlegm was believed to create a cool, calm, and unemotional temperament, known as the "phlegmatic type." This association stems from the Greek word phlegma, meaning "flame," possibly referencing the inflammation seen in colds and flus.

Phlegm also refers to a viscid mucus in the respiratory passages, often associated with illness. Figuratively, it can describe a lack of emotion, indifference, or a calm fortitude in the face of adversity. The adjective "phlegmy" describes something characterized by phlegm or a phlegmatic disposition.1234

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humour
…four cardinal humours were blood, phlegm, choler (yellow bile), and melancholy (black bile); the variant mixtures of these humours in different persons determined their “complexions,” or “temperaments,” their physical and mental qualities, and their dispositions. The ideal person had the ideally proportioned mixture of the four; a predominance of one…
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…four cardinal humours were blood, phlegm, choler (yellow bile), and melancholy (black bile); the variant mixtures of these humours in different persons determined their “complexions,” or “temperaments,” their physical and mental qualities, and their dispositions. The ideal person had the ideally proportioned mixture of the four; a predominance of one…
Read More