Source : Webster's Revised Unabridged Dictionary (1913)

Castaway \Cast"a*way\, n.
   1. One who, or that which, is cast away or shipwrecked.

   2. One who is ruined; one who has made moral shipwreck; a
      reprobate.

            Lest . . . when I have preached to others, I myself
            should be a castaway.                 --1 Cor. ix.
                                                  27.

Castaway \Cast"a*way\, a.
   Of no value; rejected; useless.

Source : WordNet®

castaway
     adj 1: suffering the misfortune of shipwreck; "shipwrecked
            sailors"; "castaways marooned on a desert island"
            [syn: {shipwrecked}]
     2: cast off as valueless [syn: {castaway(a)}, {rejected}]
     n 1: a person who is rejected (from society or home) [syn: {outcast},
           {pariah}, {Ishmael}]
     2: a shipwrecked person [syn: {shipwreck survivor}]