Any voucher or note from a merchant to a customer to provide an item the merchant has run out of at a later date for the item's current price, or (in a more literal sense) to provide a service at a later date
In social interactions, a polite way to turn down an invitation, with the implication one is simply postponing it and that another time would be acceptable
I can't go with you to the museum this Saturday, but can I take a rain check and go some other day?.
A rain check is a free ticket that is given to people when an outdoor game or event is stopped because of rain or bad weather, so that they can go to it when it is held again
If you say you will take a rain check on an offer or suggestion, you mean that you do not want to accept it now, but you might accept it at another time. Can I take a rain check on that?
a ticket stub entitling the holder to admission to a future event if the scheduled event was cancelled due to rain a promise that an unaccepted offer will be renewed in the future