[voiceofunreason]

"I call them 'unit tests' but they don't match the accepted definition of unit tests very well." -- Kent Beck, __Test Driven Development By Example__

The short version is that "unit test" did actually mean something (see Glenford Myers, __The Art of Software Testing__ or Boris Beizer, __Software Testing Techniques__), although it wasn't necessarily clear how those definitions applied to object-oriented programming (see Robert Binder, __Testing Object-Oriented Systems__).

The Test-First/TDD/XP community later made an effort to pivot to the language of "programmer test", but by the time that effort began it was already too late.

So I think you should continue to call your tests "tests" (or "checks", if you prefer the framing of James Bach and Michael Bolton).

As best I can tell - there's no historicity to the idea that "unit test" was a reference to the isolation of a tests from its peers; it's just a ret-con.