n. 1 cost incurred; payment of money. 2 (usu. in pl.) a costs incurred in doing a particular job etc. (will pay your expenses). b an amount paid to reimburse this (offered me $40 per day expenses). 3 a thing that is a cause of much expense (the house is a real expense to run). at the expense of so as to cause loss or damage or discredit to. expense account a list of an employee's expenses payable by the employer.
[ ME f. AF, alt. of OF espense f. LL expensa (money) spent, past part. of L expendere EXPEND ]