Definition of: cognate

(kog′nāt) adjective
1. Allied by blood; kindred; especially, related through females only.
2. Allied by derivation from the same source; belonging to the same stock or root: English cold and Latin gelidus are cognate words.
3. Allied in radical characteristics; having the same nature or quality.
—noun One who or that which is closely related to other persons or things. [<L cognatus <co- together + (g)natus, pp. of (g)nasci be born]