A DeveloperTest is the correct name for what the industry generally calls a UnitTest. It is a test written for developers, as distinct from an AcceptanceTest or CustomerTest, written for the OnsiteCustomers. (See Also ProgrammerTest)
A UnitTest might be a CustomerTest, if the Customer has specified a super-high level of rigor, such as for medical, avionics, high finance, etc. A UnitTest only tests details in strict isolation from each other. To test an object, you must replace all its dependencies with MockObjects. This is so the failure of one UnitTest implicates one and only one unit.
Under TestDrivenDevelopment, the failure of a DeveloperTest should implicate only the last edit. (Tip: Revert it!) This is why DeveloperTests should not abuse MockObjects. Each test case can cross more than one module, providing cross-testing.