SASEnoun [ C ]
uk/ˌes.eɪˌesˈiː/us/ˌes.eɪˌesˈiː/US UK saeabbreviation for self-addressed stamped envelope: an envelope with a stamp and your name and address on it that you send inside another envelope to an organization when you want a reply:
Please enclose an SASE with your application.
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