sleepiness (n.)

• acedia
• apathy
• boredom
• debilitation
• debility
• drowsiness
• dullness
• enervation
• enfeeblement
• ennui
• eyestrain
• faintness
• fatigue
• heaviness
• hebetude
• indifference
• languor
• lassitude
• lenitude
• lethargy
• lifelessness
• listlessness
• oscitancy
• overstrain
• passivity
• phlegm
• sloth
• slothfulness
• slowness
• sluggishness
• somnolence
• strain
• stupefaction
• stupor
• tiredness
• torpidity
• torpidness
• torpor
• weakness
• weariness
• world-weariness