Source : Webster's Revised Unabridged Dictionary (1913)

Swag \Swag\, v. i.
   To tramp carrying a swag. [Australia]

Swag \Swag\, n. [Australia]
   (a) A tramping bushman's luggage, rolled up either in canvas
       or in a blanket so as to form a long bundle, and carried
       on the back or over the shoulder; -- called also a
       {bluey}, or a {drum}.
   (b) Any bundle of luggage similarly rolled up; hence, luggage
       in general.

             He tramped for years till the swag he bore seemed
             part of himself.                     --Lawson.

Swag \Swag\, v. i. [imp. & p. p. {Swagged}; p. pr. & vb. n.
   {Swagging}.] [Cf. Icel. sveggja, sveigja to bend, to sway,
   Norw. svaga to sway. See {Sway}.]
   1. To hang or move, as something loose and heavy; to sway; to
      swing. [Prov. Eng.]

   2. To sink down by its weight; to sag. --Sir H. Wotton.

            I swag as a fat person's belly swaggeth as he goeth.
                                                  --Palsgrave.

Swag \Swag\, n.
   1. A swaying, irregular motion.

   2. A burglar's or thief's booty; boodle. [Cant or Slang]
      --Charles Reade.

Source : WordNet®

swag
     n 1: valuable goods
     2: goods or money obtained illegally [syn: {loot}, {booty}, {pillage},
         {plunder}, {prize}, {dirty money}]
     3: a bundle containing the personal belongings of a swagman
     v 1: droop, sink, or settle from or as if from pressure or loss
          of tautness [syn: {sag}, {droop}, {flag}]
     2: walk as if unable to control one's movements; "The drunken
        man staggered into the room" [syn: {stagger}, {reel}, {keel},
         {lurch}, {careen}]
     3: sway heavily or unsteadily
     [also: {swagging}, {swagged}]

Source : Free On-Line Dictionary of Computing

SWAG
     
         Scientific (or Silly) Wild Ass Guess.  A term used by
        technical teams when establishing high level sizings for large
        projects.
     
        (2000-08-09)