The Collaborative International Dictionary of English v.0.48:

Muse \Muse\, v. i. [imp. & p. p. Mused; p. pr. & vb. n.
   Musing.] [F. muser to loiter or trifle, orig., to stand
   with open mouth, fr. LL. musus, morsus, muzzle, snout, fr. L.
   morsus a biting, bite, fr. mordere to bite. See Morsel, and
   cf. Amuse, Muzzle, n.]
   1. To think closely; to study in silence; to meditate.
      "Thereon mused he." --Chaucer.
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            He mused upon some dangerous plot.    --Sir P.
                                                  Sidney.
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   2. To be absent in mind; to be so occupied in study or
      contemplation as not to observe passing scenes or things
      present; to be in a brown study. --Daniel.
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   3. To wonder. [Obs.] --Spenser. --B. Jonson.
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   Syn: To consider; meditate; ruminate. See Ponder.
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