To switch each of (two things) into the place of the other. To give and receive mutually; exchange. To cause to succeed each other in a series or pattern; alternate: interchanged gold and silver beads in the bracelet. To change places with each other. To succeed each other; alternate. The act or process of interchanging. A highway intersection that employs ramps and overpasses or underpasses to permit traffic to move freely from one road to another without crossing another line of traffic.