Etymology From Middle English fleumatik, flewmatik, flematik, fleumatyke, flewmatyk, from Old French fleumatique, from Latin phlegmaticus, from Ancient Greek φλεγματικός (phlegmatikós), from φλέγμα (phlégma), referring to the humour which ancient Hippocratic and later Galenic medicine associated with mildness, coldness, sluggishness, and indifference. Spelling later altered to resemble the word's Latin and Greek roots, with modern pronunciation following this new spelling.
1
Not easily excited to action or passion; calm; sluggish.
Calm and phlegmatic, with a clear eye, Mr. Fogg seemed a perfect type of that English composure which Angelica Kauffmann has so skilfully represented on canvas.1873, Jules Verne, chapter 2, in Around the World in 80 Days, archived from the original on 12 Apr 2012:
2013, A.O. Scott, “How It Looks to Think: Watch Her,” Rev. of Hannah Arendt, dir. by Margarethe von Trotta, New York Times 29 May 2013: C1. Print. Their friendship (immortalized in a splendid volume of letters that has clearly served as one of Ms. von Trotta's sources) is a fascinating study in cultural and temperamental contrast, an impulsive and witty American paired with a steady, phlegmatic German.
2
Generating, causing, or full of phlegm.
cold and phlegmatic bodies1650, Thomas Browne, Pseudodoxia Epidemica: […], 2nd edition, London: […] A[braham] Miller, for Edw[ard] Dod and Nath[aniel] Ekins, […], →OCLC:
Etymology From Middle English fleumatik, flewmatik, flematik, fleumatyke, flewmatyk, from Old French fleumatique, from Latin phlegmaticus, from Ancient Greek φλεγματικός (phlegmatikós), from φλέγμα (phlégma), referring to the humour which ancient Hippocratic and later Galenic medicine associated with mildness, coldness, sluggishness, and indifference. Spelling later altered to resemble the word's Latin and Greek roots, with modern pronunciation following this new spelling.