The definition of conservative is preference for old systems, policies, and power structures. There is no other definition. Conservatives are just people who resist and undo change on reflex.

What about the modern right?

They do not care about individual liberties -- because that would mean they are liberals and they tell us they are not liberals. They do not care about making a more effective and efficient government -- because that would mean they are progressives and they tell us they are not progressives. They do not care about having a fair, just society that promotes the most good for the most people -- because that would make them socialists and they tells us they are not socialists.

Normal people think many different things at once about many different subjects. It's normal to have policy preferences that are a combination of all these things are more -- including conservative preferences to avoid change for its own sake. But normal, reasonable people realize there are competing motivations and goals that have to be balanced. The right tell us they are only conservative and nothing else because they are not reasonable people.