rain check

English Thesaurus

1. a ticket stub entitling the holder to admission to a future event if the scheduled event was cancelled due to rain (noun.communication)

hypernym	:	stub, ticket stub,
definition	:	a torn part of a ticket returned to the holder as a receipt (noun.communication)

2. a promise that an unaccepted offer will be renewed in the future (noun.communication)

hypernym	:	promise,
definition	:	a verbal commitment by one person to another agreeing to do (or not to do) something in the future (noun.communication)