From WordNet (r) 3.0 (2006):
cognate
adj 1: related in nature; "connate qualities" [syn: connate,
cognate]
2: having the same ancestral language; "cognate languages"
3: related by blood [syn: akin(p), blood-related, cognate,
consanguine, consanguineous, consanguineal, kin(p)]
n 1: one related by blood or origin; especially on sharing an
ancestor with another [syn: blood relation, blood
relative, cognate, sib]
2: a word is cognate with another if both derive from the same
word in an ancestral language [syn: cognate, cognate
word]