A fixed fee is a predetermined amount of money that is paid for a service or product. It is usually a one-time payment and does not vary depending on the amount of work done. The two crossword solutions, RATE (4 letters) and SETRATE (7 letters), refer to this type of payment. RATE is a verb meaning to determine the amount of money to be paid for something, while SETRATE is a noun meaning the predetermined amount of money that is paid for a service or product.