1.NounA spending or consuming, often a disbursement of funds.
"She went to great expense to ensure her children would get the best education.; Buying the car was a big expense, but will be worth it in the long run.; We had a training weekend in New York, at the expense of our company."
2.NounThe elimination or consumption of something, sometimes with the notion of loss or damage to the thing eliminated.
"Jones reached the final at the expense of Smith, who couldn't beat him."
3.NounLoss.
4.VerbTo charge a cost against an expense account; to bill something to the company for which one works.
"It should be acceptable to expense a business lunch with a client."