phlegm vs languor

phlegm and languor both are nouns.

Word	Noun	Adjective	Verb	Adverb
phlegm	Yes	No	No	No
languor	Yes	No	No	No

As nouns, phlegm and languor are synonyms defined as:

Other synonyms of phlegm include flatness, lethargy, sluggishness.

phlegm (noun)	languor (noun)
inactivity; showing an unusual lack of energy	inactivity; showing an unusual lack of energy
expectorated matter; saliva mixed with discharges from the respiratory passages; in ancient and medieval physiology it was believed to cause sluggishness	a relaxed comfortable feeling
apathy demonstrated by an absence of emotional reactions	a feeling of lack of interest or energy
	oppressively still air