is there a more accepted connotation of the lone word "computation" that means something different from "theory of computation" (in the sense of turing machines, computability, decidability, complexity classes, Sipser) etc?

I could see someone interpreting "computation" to be more practical.

Yeah, actually computing things imo

the theory is mainly about uncomputable things tho

the Oxford joint schools degree was called "Mathematics and Computation" for many, many years

I got the impression that they thought computer science was a fad that was going to go away soon.

Yes I remember your comment to that effect on the last thread that touched on this topic! From memory I think I was ten years after you and either I had different expectations or the course had changed radically because I had a much more positive experience.

These days you can have math and real computation; proving theorems through reducing terms in Lean