The term EXACT REPETITION can be defined as an ECHO, which is a four-letter word. An ECHO is the repetition of a sound or voice caused by reflection of sound waves from a surface back to the listener. This phenomenon is often heard in nature, such as in a canyon or valley, and can also be artificially created in a recording studio. In everyday life, an ECHO can also refer to the repetition of words or phrases, such as when someone repeats what another person has said.