Not sure how much is sincere here, but a monolith typically means "not microservice architecture" and has very little-to-nothing to do with the ops side.
You're mistaken then. Monolith is just project organization. Think microservices and then realize the monolith is on the other end of the spectrum. It's in the name.
You keep posting this. A monolith is a software architecture. It says nothing about there being one instance of that monolithic process or a billion any more than "microservice architecture" becomes untrue unless you have k instances of any particular service.
It's like saying "this thing says it is built as a suspension bridge, but there are ten of them, so I wouldn't call it a bridge."
If your definition of a monolith refers to a singular server, then I've never worked on a monolith in my life. Even the crufty old ASP apps I used to work on weren't monoliths.
This would also mean that deploying a microservice architecture onto a single server, using docker for example, would be considered a monolith. Or even better, any application that leverages a database on a separate server is no longer a monolith! That's way easier than rearchitecting your whole app.
I've never come across a definition for monolith in the context of software that had anything to do with the actual infrastructure employed
Nevertheless, that's a pretty common term when the compute portion of the application is a single tier, but that doesn't mean that the tier can't scale over many stateless compute nodes.