According to "The Dictionary of Linguistics and Phonetics", these are autohyponyms. The example they use says:
...for example, a cow contrasts with a horse at one level, but at a lower level it contrasts with bull (in effect, 'a cow is a kind of cow').
Similarly, the term peacock is often used to refer to the entire family of birds, rather than calling them peafowl (and hence peahen and peachick).
I myself like a cup of coffee. No, not a mocha or a latte, just a plain coffee please.
In "Pride and Prejudice", Jane Bennet is often referred to as Miss Bennet, being the eldest of the girls. She is of course one of the Miss Bennets, but when this is used in the singular, it refers to her specifically rather than to any of her sisters.
There is a brand of fashion store called Somewhere, with many outlets which are somewhere.
While Levi's are best known for their Levi's, they also sell t-shirts and jackets in addition to their jeans.
As a final example, I offer you the word word, which is also an autonym. All autonyms are subsets of one in the set which they describe.
Coming is from the viewpoint of the destination.
You might say to your colleagues "I'm going home" then phone your partner and, if they are already there, say "I'm coming home".
While you are home you might say "I came home", though you could also say "I went home" positioning your speech relative to where you were at the time you set out on your journey.
In the imperative, you can ask someone to come to where you currently are, "please come home". You can use either come in terms of where you will also be later, "come to the club with me", though you can also use go to ask them to join you in your act of going, "go to the club with me".
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The OED calls that usage of go colloquial. It's a logical extension of the more correct usage of "go" defined as "produced sound" (i.e. "the firecracker went 'bang'"). This usage goes all the way back to the 16th century.
It's interesting to note that the earlier examples it gives refer to people making vocalizations that are not entirely words, i.e. "‘Yo-yo-yo-yo-yoe,’ went the first boy." So it seems like using "goes" instead of "says" is something that is increasing in common usage, at least in informal situations.