| 1 | Latin | phlegma | phlegm |
| 2 | Ancient Greek | φλέγμα | flame, fire, heat; inflammation; phlegm, a cold... |
| 3 | Ancient Greek | φλέγω | I set on fire, burn, scorch; I kindle, arouse,... |
| 4 | Proto-Indo-European | bʰel- | to sound; to speak, roar, bark; shiny, white; to... |
| 5 | Proto-Indo-European | bʰōl- | — |