line of descent
     n 1: the kinship relation between an individual and the
          individual's progenitors [syn: {descent}, {lineage}, {filiation}]
     2: the descendants of one individual; "his entire lineage has
        been warriors" [syn: {lineage}, {line}, {descent}, {bloodline},
         {blood line}, {blood}, {pedigree}, {ancestry}, {origin},
        {parentage}, {stemma}, {stock}]
Source: WordNet® 2.0