The Collaborative International Dictionary of English v.0.48:

Slumber \Slum"ber\, v. i. [imp. & p. p. Slumbered; p. pr. &
   vb. n. Slumbering.] [OE. slombren, slumberen, slumeren, AS.
   slumerian, fr. sluma slumber; akin to D. sluimeren to
   slumber, MHG. slummern, slumen, G. schlummern, Dan. slumre,
   Sw. slumra, Goth. slawan to be silent.]
   1. To sleep; especially, to sleep lightly; to doze. --Piers
      Plowman.
      [1913 Webster]

            He that keepeth Israel shall neither slumber nor
            sleep.                                --Ps. cxxi. 4.
      [1913 Webster]

   2. To be in a state of negligence, sloth, supineness, or
      inactivity. "Why slumbers Pope?" --Young.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Slumber \Slum"ber\, v. t.
   1. To lay to sleep. [R.] --Wotton.
      [1913 Webster]

   2. To stun; to stupefy. [Obs.] --Spenser.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Slumber \Slum"ber\, n.
   Sleep; especially, light sleep; sleep that is not deep or
   sound; repose.
   [1913 Webster]

         He at last fell into a slumber, and thence into a fast
         sleep, which detained him in that place until it was
         almost night.                            --Bunyan.
   [1913 Webster]

         Fast asleep? It is no matter;
         Enjoy the honey-heavy dew of slumber.    --Shak.
   [1913 Webster]

         Rest to my soul, and slumber to my eyes. --Dryden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

slumber
    n 1: a natural and periodic state of rest during which
         consciousness of the world is suspended; "he didn't get
         enough sleep last night"; "calm as a child in dreamless
         slumber" [syn: sleep, slumber]
    2: a dormant or quiescent state
    v 1: be asleep [syn: sleep, kip, slumber, log Z's,
         catch some Z's] [ant: wake]