SuaviloquyToday’s word

consanguinity

Consanguinity, n.

Etymology: [L. consanguinitas: cf. F. consanguintit.]

The relation of person by blood, is distinction from affinity or relation by marriage; blood relationship; as, lineal consanguinity; collateral consanguinity. Invoking aid by the ties of consanguinity. Prescott.

Shades of meaning

Fernald has no entry of its own for consanguinity; he lists it under kin.

Where he writes about it:

Affinity is relationship by marriage, consanguinity is relationship by blood. — from kin