Indicates the frequency with which interest is computed and added to the principal to arrive at a new actual balance. The essential point to remember if you are a borrower is the the less frequent the compounding, the better deal for you. If you are a Lender (or saver at the bank) the more often the frequency of compounding, the more you will get in return. In Canada, Lenders, generally compound mortgages semi-annually.

combined into or constituting a chemical compound.

Synonymous when used in connection with calculated interest paid on a mortgage.