to accept that an amount of money has been lost or that a debt will not be paid

The World Bank is being urged to write off debts from developing countries. 一些机构正敦促世界银行免除发展中国家的债务。

to be able to use the cost of something you have bought to reduce the amount of tax you owe

You might be able to write off the car as a business expense. 你也许可以把那辆车作为业务支出而避免交税。

to damage a vehicle so badly that it cannot be repaired

His car was completely written off in the accident. 他的车在事故中完全报废。

to decide that a particular person or thing will not be useful, important, or successful

A lot of companies seem to write people off if they're over 50. 很多公司似乎认为员工一超过50岁就无所作为了。