The Collaborative International Dictionary of English v.0.48:

Robbery \Rob"ber*y\, n.; pl. Robberies. [OF. roberie.]
   1. The act or practice of robbing; theft.
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            Thieves for their robbery have authority
            When judges steal themselves.         --Shak.
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   2. (Law) The crime of robbing. See Rob, v. t., 2.
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   Note: Robbery, in a strict sense, differs from theft, as it
         is effected by force or intimidation, whereas theft is
         committed by stealth, or privately.
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   Syn: Theft; depredation; spoliation; despoliation;
        despoilment; plunder; pillage; rapine; larceny;
        freebooting; piracy.
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WordNet (r) 3.0 (2006):

robbery
    n 1: larceny by threat of violence
    2: plundering during riots or in wartime [syn: looting,
       robbery]