Source : Webster's Revised Unabridged Dictionary (1913)

Samurai \Sa"mu*rai`\, n. pl. & sing. [Jap.]
   In the former feudal system of Japan, the class or a member
   of the class, of military retainers of the daimios,
   constituting the gentry or lesser nobility. They possessed
   power of life and death over the commoners, and wore two
   swords as their distinguishing mark. Their special rights and
   privileges were abolished with the fall of feudalism in 1871.

Source : WordNet®

samurai
     n 1: a Japanese warrior who was a member of the feudal military
          aristocracy
     2: feudal Japanese military aristocracy

Source : Free On-Line Dictionary of Computing

samurai
     
        A hacker who hires out for legal cracking jobs, snooping for
        factions in corporate political fights, lawyers pursuing
        privacy-rights and First Amendment cases, and other parties
        with legitimate reasons to need an electronic locksmith.  In
        1991, mainstream media reported the existence of a loose-knit
        culture of samurai that meets electronically on BBS systems,
        mostly bright teenagers with personal micros; they have
        modelled themselves explicitly on the historical samurai of
        Japan and on the "net cowboys" of William Gibson's {cyberpunk}
        novels.  Those interviewed claim to adhere to a rigid ethic of
        loyalty to their employers and to disdain the vandalism and
        theft practiced by criminal crackers as beneath them and
        contrary to the hacker ethic; some quote Miyamoto Musashi's
        "Book of Five Rings", a classic of historical samurai
        doctrine, in support of these principles.
     
        See also {Stupids}, {social engineering}, {cracker}, {hacker
        ethic}, and {dark-side hacker}.
     
        [{Jargon File}]