Closing the books refers to the act of finalizing the accounting records of a business at the end of a fiscal year. There are several synonyms for this term, including 'year-end close', 'financial close', and 'period-end close'. While these terms all essentially mean the same thing, each has a slightly different connotation. Year-end close is the most common and straightforward, while financial close emphasizes the financial aspect of the process. Period-end close is a more general term that could refer to a monthly or quarterly close, as well as the annual close. Ultimately, the specific term used may depend on the individual company or industry jargon.