1. Commercial and corporate finance.
In a commercial context, the business entity refers to the whole of the business undertaking, regardless of whether it is financed by equity alone or by a combination of equity and debt.
The Entity Value is therefore the total value of the Equity plus the Debt. In this context the entity is also sometimes known as the Enterprise (and the entity value is also known as the Enterprise Value).
2. Financial reporting - accounting practices.
In financial reporting, the reporting entity is the reporting unit for which financial information is summarised and presented.
For example a company or a group of companies.
A tax entity is a business unit which is subject to taxation.
For example a company or a branch of a company established in another country.
4. Separately identifiable unit.
More broadly, an entity may be any corporation, organisation or person that exists as a separately identifiable unit.
Evidence of being 'separately identifiable' would include the ability to produce a meaningful and complete set of financial reporting information if it were required.