Variable rate
A variable-rate loan has an interest rate that moves with a market benchmark, usually Euribor: the monthly payment can rise or fall.
The rate is reviewed at regular intervals set in the contract. It often starts lower than a fixed rate, but the borrower bears the risk of rising rates.
Some contracts cap the change, or allow switching to a fixed rate along the way. Before choosing, it helps to check that the budget could absorb a higher payment.