Bounce Message

/bau̇n(t)s me-sij/

[UNIX]

n. Notification message returned to sender by a site unable to relay email to the intended Internet address recipient or the next link in a bang path (see bounce). Reasons might include a nonexistent or misspelled username or a down relay site. Bounce messages can themselves fail, with occasionally ugly results; see sorcerer's apprentice mode. The term 'bounce mail' is also common.