Refrigerator and freezer both are the ususal expression. Sometimes they can be called the same series of products, but actually there are some differences to a very small extent.

A refrigerator is a large container which is kept cool inside, usually by electricity, so that the food and drink in it stays fresh.

A freezer is a large container like a fridge in which the temperature is kept below freezing point so that you can store food inside it for long periods.

In general, the meaning of freezer is larger than that of refrigerator.