acedia
adynamia
anemia
apathy
atony
blah feeling
bloodlessness
blues
boredom
brain fag
cachexia
cachexy
cowardice
debilitation
debility
depression
disinterest
disregard
doldrums
drowsiness
dullness
dumps
enervation
enfeeblement
ennui
etiolation
exhaustion
eyestrain
faintness
fatigue
feebleness
flabbiness
flaccidity
goneness
heart strain
heaviness
hebetude
heedlessness
impotence
inanimation
indifference
insouciance
jadedness
lackadaisicalness
languidness
languishment
languor
weakness
deadness
despondency
discouragement
dizziness
laziness
lethargy
listlessness
malaise
nervousness
numbness
tiredness
torpor
weariness