What is the linguistic explanation of the phenomenon in "affirmative action"?

Question

The phrase "affirmative action" does not tell you what it is about. Even though the literal meaning of this phrase can be very broad (in theory it could be referring to affirmative action of achieving anything), but it is commonly used to refer to a very specific kind of affirmative action. What really matters is the specifics, which is the core meaning of the phrase but not captured within the phrase. For someone who does not know the context of the discussion, the phrase can be very confusing.

It is kind of like using the word "dog" refer to a specific kind of dog. And then in the whole public discussion of that specific kind of dog, it never has a specific name, just called "dog". This is not a good example, but hope you know what I mean.

Is there a linguistic term for this kind of phenomenon? What are the other examples of this kind of usage?

Answer 1

This phenomenon is called Specialization, a process in which a lexical term decreases in scope.

There are five basic Grammaticalization processes that you may find interesting to learn about.

Quite often, Euphemisms use neutral or generic words to mask taboo topics or profanity. Quoting the Wikipedia article linked above,

Affirmative action, meaning a preference for minorities or the historically disadvantaged, usually in employment or academic admissions. This term is sometimes said to be a euphemism for reverse discrimination, or in the UK positive discrimination, which suggests an intentional bias that might be legally prohibited, or otherwise unpalatable.

The Specialization can be combined with the adoption of a loanword. One example is that in Ukrainian, we have a generic word for dog, /sobaka/. However, a certain breed of dogs, Great Dane (plus several others) are called literally /dog/.