Emily Dickinson Lexicon

PHLEGM, n. [flem; Gr. φλεγμα, inflammation, and pituitous matter, from φλεγω, to burn; hence the word must have originally expressed the matter formed by suppuration.]

1. Cold animal fluid; watery matter; one of the four humors of which the ancients supposed the blood to be composed. Coxe. Encyc.
2. In common usage, bronchial mucus; the thick viscid matter secreted in the throat.
3. Among chimists, water, or the water of distillation. Coxe.
4. Dullness; coldness; sluggishness; indifference.