Is printed the same as published?
"Published" is a vague word, since for example you can even self-publish a book.
Ideally, a published book will have been carefully selected and edited, widely distributed, archived in many libraries, etc. How close it comes to this ideal varies, of course.
I don't know whether what you are describing would meet a formal definition of publication, but I'd be careful about how you describe it.
For example, if your book has an ISBN, is labeled with a publisher like "X University Press", and is publicly offered for sale (perhaps only through the university's website and university bookstore), then I would consider it published, even if only on a small scale. (It may be cheap, but there's no requirement that a published book must have gilded pages.) However, that sounds unlikely to be true in the case you've described.
Instead, you could describe it in other ways:
If anyone who wants a copy can buy one by getting in touch with your department, then you could describe it as a "book distributed by the Department of ... at University X".
If your book is not offered for sale to anyone except students in the course, then you might describe it as a "book prepared as course materials for ... at University X".
You might also want to specify something like the number of pages, to help distinguish between a lengthy book and shorter lecture notes.