The Collaborative International Dictionary of English v.0.48:

Ancestry \An"ces*try\, n. [Cf. OF. ancesserie. See Ancestor.]
   1. Condition as to ancestors; ancestral lineage; hence, birth
      or honorable descent.
      [1913 Webster]

            Title and ancestry render a good man more
            illustrious, but an ill one more contemptible.
                                                  --Addison.
      [1913 Webster]

   2. A series of ancestors or progenitors; lineage, or those
      who compose the line of natural descent.
      [1913 Webster]

WordNet (r) 3.0 (2006):

ancestry
    n 1: the descendants of one individual; "his entire lineage has
         been warriors" [syn: lineage, line, line of descent,
         descent, bloodline, blood line, blood, pedigree,
         ancestry, origin, parentage, stemma, stock]
    2: inherited properties shared with others of your bloodline
       [syn: ancestry, lineage, derivation, filiation]

Moby Thesaurus II by Grady Ward, 1.0:

104 Moby Thesaurus words for "ancestry":
   affiliation, agnate, agnation, alliance, aristocracy,
   aristocraticalness, birth, blood, blood relation,
   blood relationship, blood relative, blue blood, breed, breeding,
   brotherhood, brothership, clansman, cognate, cognation, collateral,
   collateral relative, common ancestry, common descent, connection,
   connections, consanguinean, consanguinity, cousinhood, cousinship,
   derivation, descent, distaff side, distant relation, distinction,
   enate, enation, extraction, family, fatherhood, filiation, flesh,
   flesh and blood, folks, fraternity, genteelness, gentility, german,
   honorable descent, kin, kindred, kinfolk, kinnery, kinsfolk,
   kinship, kinsman, kinsmen, kinswoman, kith and kin, line, lineage,
   maternity, matrilineage, matriliny, matrisib, matrocliny,
   motherhood, near relation, next of kin, nobility, noble birth,
   nobleness, origin, paternity, patrilineage, patriliny, patrisib,
   patrocliny, pedigree, people, posterity, propinquity, quality,
   race, rank, relation, relations, relationship, relatives, royalty,
   sib, sibling, sibship, sisterhood, sistership, source, spear kin,
   spear side, spindle kin, spindle side, stock, sword side,
   ties of blood, tribesman, uterine kin