WordNet (r) 3.0 (2006):

bloodline
    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: ancestry of a purebred animal [syn: pedigree, bloodline]

Moby Thesaurus II by Grady Ward, 1.0:

34 Moby Thesaurus words for "bloodline":
   affiliation, apparentation, birth, blood, branch, breed,
   common ancestry, consanguinity, derivation, descent, direct line,
   distaff side, extraction, family, female line, filiation, house,
   line, line of descent, lineage, male line, phylum, race, seed,
   sept, side, spear side, spindle side, stem, stirps, stock, strain,
   succession, sword side