autoresponder Syllabification: (au·to·re·spond·er)Pronunciation: /ˌätōrəˈspändər/Definition of autoresponder noun Computing a program that automatically generates a set response to all messages sent to a particular e-mail address: I got a reply almost right away, which I assume was from an autoresponderautoresponder in other Oxford dictionaries Definition of autoresponder in the British & World English dictionary