Nouns

(n)emotionlessness, impassivity, impassiveness, phlegm, indifference, stolidity, unemotionalityapathy demonstrated by an absence of emotional reactions
(n)phlegm, sputumexpectorated matter; saliva mixed with discharges from the respiratory passages; in ancient and medieval physiology it was believed to cause sluggishness
(n)languor, lethargy, sluggishness, phlegm, flatnessinactivity; showing an unusual lack of energy“the general appearance of sluggishness alarmed his friends”