consanguineousadjective
/ˌkɒn.sæŋˈɡwɪn.i.əs//ˌkɑːn.sæŋˈɡwɪn.i.əs/specializedconnected with the fact of people being blood relations (= related to someone by birth, not marriage):
Some Hindu groups prefer consanguineous marriages while others prohibit them.