Source : Webster's Revised Unabridged Dictionary (1913)

Boss \Boss\, n. [D. baas master.]
   A master workman or superintendent; a director or manager; a
   political dictator. [Slang, U. S.]

Boss \Boss\ (b[o^]s; 115), n.; pl. {Bosses} (-[e^]z). [OE. boce,
   bose, boche, OF. boce, boche, bosse, F. bosse, of G. origin;
   cf. OHG. b[=o]zo tuft, bunch, OHG. b[=o]zan, MHG. b[^o]zen,
   to beat. See {Beat}, and cf. {Botch} a swelling.]
   1. Any protuberant part; a round, swelling part or body; a
      knoblike process; as, a boss of wood.

   2. A protuberant ornament on any work, either of different
      material from that of the work or of the same, as upon a
      buckler or bridle; a stud; a knob; the central projection
      of a shield. See {Umbilicus}.

Boss \Boss\ (b[o^]s), v. t. [imp. & p. p. {Bossed} (b[o^]st); p.
   pr. & vb. n. {Bossing}.] [OE. bocen, fr. OF. bocier. See the
   preceding word.]
   To ornament with bosses; to stud.

Source : WordNet®

boss
     n 1: a person who exercises control over workers; "if you want to
          leave early you have to ask the foreman" [syn: {foreman},
           {chief}, {gaffer}, {honcho}]
     2: a person responsible for hiring workers; "the boss hired
        three more men for the new job" [syn: {hirer}]
     3: a person who exercises control and makes decisions; "he is
        his own boss now"
     4: a leader in a political party who controls votes and
        dictates appointments; "party bosses have a reputation for
        corruption" [syn: {party boss}, {political boss}]
     5: a circular rounded projection or protuberance [syn: {knob}]
     v : raise in a relief; "embossed stationary" [syn: {emboss}, {stamp}]

boss
     adj : exceptionally good; "a boss hand at carpentry"; "his brag
           cornfield" [syn: {brag}]

Source : Free On-Line Dictionary of Computing

BOSS
     
        Bridgport Operating System Software.  A derivative of the {ISO
        1054} numerical machine control language for milling, etc.