The Collaborative International Dictionary of English v.0.48:

Rob \Rob\, n. [F.; cf. Sp. rob, It. rob, robbo, Pg. robe,
   arrobe, Ar. rubb, robb, Per. rub.]
   The inspissated juice of ripe fruit, obtained by evaporation
   of the juice over a fire till it acquires the consistence of
   a sirup. It is sometimes mixed with honey or sugar. [Written
   also rhob, and rohob.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Rob \Rob\, v. t. [imp. & p. p. Robbed; p. pr. & vb. n.
   Robbing.] [OF. rober, of German origin; cf. OHG. roub?n, G.
   rauben, and OHG. roub robbing, booty, G. raub. [root]114. See
   Reave,and cf. Robe.]
   1. To take (something) away from by force; to strip by
      stealing; to plunder; to pillage; to steal from.
      [1913 Webster]

            Who would rob a hermit of his weeds,
            His few books, or his beads, or maple dish?
                                                  --Milton.
      [1913 Webster]

            He that is robbed, not wanting what is stolen,
            Let him not know it, and he's not robbed at all.
                                                  --Shak.
      [1913 Webster]

            To be executed for robbing a church.  --Shak.
      [1913 Webster]

   2. (Law) To take the property of (any one) from his person,
      or in his presence, feloniously, and against his will, by
      violence or by putting him in fear.
      [1913 Webster]

   3. To deprive of, or withhold from, unjustly or injuriously;
      to defraud; as, to rob one of his rest, or of his good
      name; a tree robs the plants near it of sunlight.
      [1913 Webster]

            I never robbed the soldiers of their pay. --Shak.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Rob \Rob\, v. i.
   To take that which belongs to another, without right or
   permission, esp. by violence.
   [1913 Webster]

         I am accursed to rob in that thief's company. --Shak.
   [1913 Webster] Robalo

WordNet (r) 3.0 (2006):

rob
    v 1: take something away by force or without the consent of the
         owner; "The burglars robbed him of all his money"
    2: rip off; ask an unreasonable price [syn: overcharge,
       soak, surcharge, gazump, fleece, plume, pluck,
       rob, hook] [ant: undercharge]

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "rob":
   bereave, cheat, commit robbery, defraud, despoil, disinherit,
   dispossess, divest, filch, heist, hijack, hold up, hustle,
   knock off, knock over, lift, loot, lose, mug, oust, pilfer,
   pillage, plunder, purloin, ransack, ravage, relieve, rifle,
   rip off, roll, sack, steal, stick up, strong-arm, swindle,
   thieve