You already worked out what CI/CD is an abbreviation for, so I won't repeat it.

When someone says CI, usually they mean "whatever is responsible for running tests on each pull request". The Wikipedia page for CI: https://en.wikipedia.org/wiki/Continuous_integration says a bunch of stuff but none of that is what people actually mean when they say CI, people really just mean something on a server somewhere runs something on your code when you push it.

Someone, somewhere, is probably talking about "CI" on their never-integrated long-lived feature branch which isn't continuously integrated with anything.

The "CD" part of CI/CD is horrific - the fact that it can mean either continuous deployment or delivery, which allegedly have distinct meanings (can never remember which is which), is terrible.

A real failure of terminology.