What is a “service lecture”? On a form for a job application, I am being asked to list, among others, what “service lectures” I have given. What exactly is meant by that? What does, or does not, count as a service lecture?
In my experience, service lecture is used to refer to a lecture (course) about your field given to students of another field, usually an introductory course to give those students the basics that they need for their studies.

For example, at my university, there is a course Physics for Chemists, Biologists, and Geologists which is organised by the department of physics and given by a physics professor and which teaches essential concepts of physics to students of the named fields. In contrast to “physics for physicists” lectures, the department of physics does not benefit from the effort put into this lecture as it’s not teaching its own students. Thus giving this lecture is a mere service to the departments of chemistry, biology and geology.

Of course, to be sure about the intended meaning, you would have to ask the issuers of the form.