The acronym CPA stands for Certified Public Accountant. A CPA is a professional who has passed the Uniform CPA Examination and has met additional state education and experience requirements for certification as a CPA. The NOS in the crossword solution stands for National Association of State Boards of Accountancy, which is an organization that provides support to state boards in their regulation of the CPA profession. The CERT in the crossword solution stands for Certified Public Accountant, which is the title given to individuals who have met the requirements to become a CPA.