[nabla9]

A student's union is not the same as a labor union. The student's union represents students.

This is a labor union representing graduate student-workers who are employed by MIT.

[some-human]

Again, The staff of the university (academics, lecturers, trainers, instructors, researchers, etc) tend to belong to The University and College Union.[2]

If they are employed by the university in the UK, they typically belong to this union.