A practical definition of what makes up a company’s culture:
I’ve been working in HR for over twenty years, and the best companies I’ve worked with have recognized that there are three elements to a culture: behaviors, systems, and practices, all guided by an overarching set of values. A great culture is what you get when all three of these are aligned, and line up with the organization’s espoused values. When gaps start to appear, that’s when you start to see problems — and see great employees leave.
This could work as a good checklist of items to assess if you do have gaps between stated values and actual actions.