Settle up is a term used to describe the process of paying or repaying a debt. The three crossword solutions for this term are PAY (3 letters), REPAY (5 letters), and REMIT (5 letters). Paying or repaying a debt can be done in a variety of ways, such as cash, check, or online payment. Repaying a debt usually involves returning the same amount of money that was borrowed, plus any additional fees or interest. Remitting a debt is similar to repaying a debt, but it usually involves sending the money to a third party, such as a collection agency.