The term "bank customer" is a broad category that refers to individuals or businesses who hold an account at a financial institution. Synonyms for this term might include "account holder," "client," "deposit holder," "member," or "patron." These terms all refer to someone who maintains some level of financial activity with a bank or credit union, whether that involves depositing funds, obtaining loans or credit, or utilizing the bank's other services. Each of these synonyms captures a slightly different nuance, but all of them ultimately represent the same central idea: a person or entity that interacts with a financial institution on some level.