Numbers, letters, or alphanumeric code assigned to every significant customer, supplier, and lender for ease of reference in an organization's accounting records.
I can order them for you, if you give me your account number.

the amount of money that you have to pay for something such as a service
That store charges an extra amount for home delivery.

the amount of space between two points
The distance between Newcastle and Sydney is about 160 km.

owed to a person as a right
The assignment is due tomorrow.

the distance from one end of something to the other
The river is 300 miles in length.

the act of giving money for something
The payment will come due next month.

the current price for something
The rate is 50 dollars a day.