Ask 12 developers and you'll get 12 different answers, but what do you think? What are the "units" being tested in "unit tests"?
@jasongorman I prefer "component test" because that's the key difference. You're testing individual components to ensure they behave as expected.
@JonHAyre Component as in "unit of software release"?
@jasongorman Component as in a self-contained piece of code that performs a generic task. E.g. a reusable class in object oriented development. Also components can contain other components. An analogy: a spark plug is a component, as is the engine into which it is fitted. Each can be tested in isolation to ensure it behaves as required. The car is the product into which the components are installed. Component tests make sense independently for the component as well as for the system as a whole.
@jasongorman hence the unit/component test is itself a system into which you fit the component to be tested, akin to a test rig in engineering terms.