Depending on the size of the business and the owner's preference, the business owner can be called anything they want; the most common names for business owners are business owner and chief executive officer. Larger companies usually refer to the owner of their company as the CEO, while smaller companies simply refer to their business owner as the owner.
There is no specific name for a business owner, and the name that the owner is called is simply a preference of the business owner and what the employees are comfortable calling him or her. It is important for employees to address the business owner by the name he or she prefers.
There are many small businesses in the United States, and many of the owners of these businesses do not go by CEO, but rather business owner. The CEO title is often reserved for larger companies where there are several owners who have put time and money into the business. The CEO is the go-to person that stands with the rest of the owners, but is the face of the ownership. The CEO handles daily operations that involve the company while the rest of the owners can work behind the scenes.