From The Collaborative International Dictionary of English v.0.48:
Cognate \Cog"nate\, a. [L. cognatus; co- + gnatus, natus, p. p.
of nasci, anciently gnasci, to be born. See Nation, and cf.
Connate.]
1. Allied by blood; kindred by birth; specifically (Law),
related on the mother's side.
[1913 Webster]
2. Of the same or a similar nature; of the same family;
proceeding from the same stock or root; allied; kindred;
as, a cognate language.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Cognate \Cog"nate\, n.
1. (Law) One who is related to another on the female side.
--Wharton.
[1913 Webster]
2. One of a number of things allied in origin or nature; as,
certain letters are cognates.
[1913 Webster]