As much as we need someone to define what is http, TCP/IP or Posix we also need someone to define what is English, Spanish or any language.
If you don't believe it then try to understand whatever language a Venezuelan or Dominican speaks. That blabber is anything but Spanish.
Why? Humans are almost infinitely more adaptable and capable of dynamically changing their behaviour compared to computer programs. Learning to understand/speak a new pseudo dialect of your native language isn't particularly hard. Millions of people do that near effortlessly on a daily basis (especially in many German speaking areas).
[1] https://en.wikipedia.org/wiki/Association_of_Academies_of_th...