No. A reboot is the restart of series or franchise and discards the continuity in order to create an entirely new one; that's something completely different from a remake. An example of a reboot would be Rise of the Planet of the Apes.
A port with small enhancements or additional content is actually just called a port; sometimes an enhanced port to acknowledge the enhancements. Skies of Arcadia Legends, for example, is a port despite all the new content, graphical touch ups, and gameplay tweaks.
A remaster is a new edition that replaces outdated assets and codework/engines in order to bring an existing game to a new generation. This is what Xenoblade Chronicles Definitive Edition is. Just because it's a more extensive remaster than other remasters does not suddenly make it something completely different.
A remake is a new take on the same story. It's not just an asset swap or a code/engine update, it's an entirely new design which attempts to recapture the original, but not replicate it. A current trend in film is live action remakes of animated films, this is a good illustration for what a game remake is because the macro-concept is directly translatable between the two industries. "Final Fantasy Remake" fits the definition of a remake to a T.
Well, what is it, a re-imaging or a reboot? A reimagining is not a type of reboot, it's a type of remake. It differs from a standard remake by creating a new franchise or universe; characters, and everything. Xenoblade Chronicles can be considered a reimagining of Xenogears since the game, on the bare bones conceptual level, is based on Xenogears with much of the plot points being remade. But by far the most prominent example of a reimagining is Star Wars vs The Hidden Fortress, and that is the best way to illustrate the term.
A big clue that Xenoblade Chronicles Definitive Edition is a remaster is the definitive edition written right into its title. The same thing can be said about Final Fantasy 7 Remake.
What you are trying to do is to use semantical fan logic to redefine well-established industry terminology in order to elevate something beyond what it actually is, like the whole "Metroid is an RPG because you play the role of Samus." In the end, it's an exercise in pretentiousness.
And Curl-6, my sincerest apologies for continuing the derail over someone's fanboy nitpick of one of my posts. But I suffer from German cultural flaws, like arguing about trivial details.
Don't quote me or at me again because it's hilarious how wrong you are but this is the hill you die on