@yaxu I mean, you can slice things as you like and defines things arbitrarily (and with any level of fuzziness and change over time) - this is exactly what we use natural language for.
However, a common and useful categorisation of 'programming languages' contra 'natural language' is that programming languages are primarily intended and used to program a computer without having to interact directly with machine specifics, and other uses are secondary. PL are primarily computer abstractions.