syn•graft(sin′graft′, -gräft′),USA pronunciationn.[Surg.]a tissue or organ transplanted from one member of a species to another, genetically identical member of the species, as a kidney transplanted from one identical twin to the other. Also called isograft, isoplastic graft, syn•ge•ne′ic graft′(sin′jə nē′ik).USA pronunciation Cf. allograft, autograft, xenograft.