The Collaborative International Dictionary of English v.0.48:

Survivor \Sur*viv"or\, n.
   1. One who survives or outlives another person, or any time,
      event, or thing.
      [1913 Webster]

            The survivor bound
            In filial obligation for some term
            To do obsequious sorrow.              --Shak.
      [1913 Webster]

   2. (Law) The longer liver of two joint tenants, or two
      persons having a joint interest in anything. --Blackstone.
      [1913 Webster]

WordNet (r) 3.0 (2006):

survivor
    n 1: one who lives through affliction; "the survivors of the
         fire were taken to a hospital" [syn: survivor,
         subsister]
    2: one who outlives another; "he left his farm to his survivors"
    3: an animal that survives in spite of adversity; "only the
       fittest animals were survivors of the cold winters"

Bouvier's Law Dictionary, Revised 6th Ed (1856):

SURVIVOR. The longest liver of two or more persons.
     2. In crises of partnership, the surviving partner is entitled to have
all the effects of the partnership, and, is bound to pay all the debts owing
by the firm. Gow on Partn. 157; Watson on Partn. 364. He is, however, bound
to account for the surplus to the representatives of his deceased partners,
agreeably to their respective rights.
     3. A surviving trustee is generally vested with all the powers of all
the trustees, and the surviving administrator is authorized to act for the
estate as if he had been sole administrator. As to the presumption of
survivorship, when two or more persons have perished by the same event, see
Civ. Code of Lo. art. 930 to 933 and vide Death; Cro. Eliz. 503; 1 Bl. Rep.
610 2 Phillim. Rep. 261; S. C. 1 Eccl. Reports, 250; Fearne on Rem. iv.;
Poth. on Obli. by Evans, vol. 2, p. 346; 8 Ves. 10; 14 Ves. 578 17 Ves. 482;
6 Taunt. 213; Cowp. 257; 5 Ves. 485. Vide, generally, 2 Fonb. Eq. 102; 8
Vin. Ab. 323; 20 Vin. Ab. 146; 8 Com. Dig. 475, 594; 1 Suppl. to Ves. jun.
115, 186, 407, 8, 2 Suppl. to Ves. jun. 47, 296, 340, 391,477; 1 Fodere,
Med. Leg. Sec. 424-483.
     4. The right of survivorship among joint-tenants has been abolished,
except as to estates held in trust, in Pennsylvania, New York, Kentucky,
Virginia, Indiana, Missouri, Tennessee, Alabama, Georgia, North and South
Carolina. Vide Estates in Joint-tenancy. In Connecticut it never existed. 1
Swift's Dig. 102 see 1 Hill. Ab. 440. As to survivorship among legatees, see
1 Turn. & R. 413; 1 Br. C. C. 574; 3 Russ. 217. See Death; Estates in Joint-
tenancy; Joint-tenants; Partnership.