The Collaborative International Dictionary of English v.0.48:

patrilineage \patrilineage\ n.
   The line of descent traced through the paternal side of the
   family.

   Syn: agnation.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

patrilineage
    n 1: line of descent traced through the paternal side of the
         family [syn: patrilineage, agnation]

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "patrilineage":
   affiliation, agnation, alliance, ancestry, blood,
   blood relationship, brotherhood, brothership, cognation,
   common ancestry, common descent, connection, consanguinity,
   cousinhood, cousinship, enation, fatherhood, filiation, fraternity,
   kindred, kinship, maternity, matrilineage, matriliny, matrisib,
   matrocliny, motherhood, paternity, patriliny, patrisib, patrocliny,
   propinquity, relation, relationship, sibship, sisterhood,
   sistership, ties of blood