sleep

[1]	doze , (take a) nap , catnap , rest , repose , slumber , drowse , drop/nod off , be in the land of Nod , be in the arms of Morpheus , snore , (Colloq) snooze , saw wood , catch/log a few zees (Z's) , take/have a zizz , catch forty winks
[2]	kip , slumber , log Z's , catch some Z's

[1]	slumber
[2]	sopor , nap , doze , slumber , rest , siesta , (Colloq) forty winks , snooze , zizz , beauty sleep
[3]	nap
[4]	rest , eternal rest , eternal sleep , quietus