Answer:
If this is a mortgage loan, it is called an adjustable rate mortgage (ARM) or if it is some other type of loan it is simply called an adjustable rate loan.
The name basically tells us everything about this type of loans, their interest rate varies and is adjusted periodically. The periods and adjustments vary depending on the specific loan, e.g. the Quimbys' loan is adjusted after 5 years, this period can be shorter or longer depending on the specific loan agreement.
