1 to put an earlier date on (a cheque/check etc): He should have paid his bill last month and so he has backdated the cheque/check.
az: keçmiş/əvvəlki tarixi yazmaq
ru: помечать задним числом
2 to make payable from a date in the past: Our pay rise/raise was backdated to April.
az: keçmiş/əvvəlki tarixlə yazmaq
ru: проводить задним числом