1. (v. t.) To put in relation or connection with each other; to connect together by mutual relation; as, to correlate natural phenomena\.

2. (v. i.) To have reciprocal or mutual relations; to be mutually related.

3. (n.) One who, or that which, stands in a reciprocal relation to something else, as father to son; a correlative.

ally alter ego analogon analogue apply associate bind bracket brother close copy close match cognate companion complement congenator congener connect coordinate corelate correlative correspondent counterpart couple draw a parallel each other equate equivalent fellow identify image interrelate kindred spirit like likeness link match mate near duplicate obverse one another parallel parallelize pendant picture reciprocal reciprocatist reciprocator relate relativize second self similitude simulacrum sister soul mate such suchlike tally the like of the likes of tie twin wed