to write a date on a cheque that is later than the date when you are signing it, so that it does not become effective until then
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post-date UK US (also postdate) verb [T]
► to write a date on a document, especially a cheque, that is later than the date on which you are writing it: »
If you cannot trust the salesman to wait until the date on a cheque before presenting it, then post-dating it is pointless.
»We always pay our credit card bill by post-dated cheque for encashment on the due date.
»a postdated letter of resignation
► UK to make something such as a payment become effective at a later date: be post-dated »
The company has a lot of orders that were postdated until January
► to happen or exist after something: »
The new terms and conditions, which postdate the time you used your card, state that if you make a charge in a currency other than sterling, that charge will be converted into sterling.
Financial and business terms. 2012.