1. alternate from one direction or person to another
pace/chat/have a back and forth
In terms of movement, 'back and forth' means to move repeatedly from one place to another. Figuratively, this term can be used in reference to communication that goes to and from one person to another, and it implies a lack of progress: "I am sick of all these emails back and forth. Can we please come to a decision?" This phrase can be used in professional and social contexts.