According to Skinner, an echoic occurs when a verbal response has point-to-point correspondence to its preceding verbal stimulus. It is echoing what is heard or verbal imitation.
Autism and Behavioral Blog
Verbal Behavior (VB) is one of the many branches under the family of Applied Behavior Analysis (ABA). Just like ABA, VB is also derived from the philosophy of behaviorism, utilizes the basic scientific methodology for research, and is concerned with the improvement of an individual's educationally and socially significant behaviors.