A person who is related to another by birth rather than by marriage. noun. A person related to another by birth rather than by marriage or adoption. noun.

What does blood relation mean?

: someone who has the same parents or ancestors as another : blood relative.

Is spouse a blood relation?

Spouse cannot be regarded to be a blood relative. Otherwise too, marriage is not permissible within certain degree of relationship. So spouse is part of same family but not blood relation.