'Cognation' definitions:

Definition of 'cognation'

noun

Line of descent traced through the maternal side of the family [syn: matrilineage, enation, cognation]

noun

(anthropology) related by blood [syn: consanguinity, blood kinship, cognation] [ant: affinity]

From: GCIDE

Cognation \Cog*na"tion\, n. [L. cognatio.]
1. Relationship by blood; descent from the same original; kindred. [1913 Webster]
As by our cognation to the body of the first Adam. --Jer. Taylor. [1913 Webster]
2. Participation of the same nature. --Sir T. Browne. [1913 Webster]
A like temper and cognation. --Sir K. Digby. [1913 Webster]
3. (Law) That tie of consanguinity which exists between persons descended from the same mother; -- used in distinction from agnation. [1913 Webster]