to write an earlier date on a cheque or other document than the date at the time of writing 倒填日期（在支票或其他文件上填上比实际日期早的日期）
() (usually be backdated) to make sth, especially a payment, take effect from an earlier date （使）付款等在较早的日期生效◆Postal workers are getting a 5% pay rise, backdated to March. 邮政员工加薪 5%，追溯到三月份起计算。