APR

Annual Percentage Rate (APR) is the yearly interest rate you would pay on top of the loan amount you have borrowed. 

For example;

You want to borrow £150,000 for a term of one year. 

The APR is a fixed 6.1% for one year. 

At the end of the term, you'd have to pay 6.1% of the £150,000, in addition to the £150,000. 

You'd be paying back the lender £9,150 in interest.

So the total to payback would be £159,150.