ACT NUM is a term used to refer to the identification number assigned to an individual's ACT test. There are various synonyms that can be used interchangeably with ACT NUM. These include ACT identification number, ACT code, ACT registration number, ACT student identification, and ACT reference number. These terms are all used to identify and keep track of an individual's ACT scores and registration information. Whether it is called an ACT NUM, ACT code, or ACT registration number, it serves the same purpose of uniquely identifying each test taker and their associated test scores.