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Somnolent
adj. sleepy, drowsy
Soporific
adj. causing sleep or fatigue
Sopor
n. sleep; drowsiness
Languid
adj. lacking energy; weak
Languish
v. to waste away
Languor
n. a lack of physical or mental energy
Vigilant
adj. on the alert; watchful
Vigilante
n. someone who takes law enforcement into his or her own hands
Acquiesce
v. to give in
Requiem
n. a song or religious service for the dead or lost
Quittance
n. a repayment; compensation