Accepted and Semi Accepted terms are:
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Interstellar
This means; travelling from one star to another.
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Sol
The 'official' name for our star. Which makes us part of the 'Sol System'. 'Sun' is just a nickname we give to our star as it has nourished us.
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Terra
The 'official' name for our planet. 'Earth' is just a nickname for the home we love.
Luna
The 'official' name for our Moon. 'The Moon' is just a nickname for our beloved companion satellite.
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Intersolar
This means; travelling from one body in our solar system to another.
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Interastral
This means; travelling from one body in our solar system to another outside of our solar system but not to another star.
The Oort Cloud is part of human 'territory' without a doubt, however is it not 'part of the Solar system in my estimation. FWIW IMHO.. Think of the Oort Cloud, like our garden wall, the Kuiper Belt as our Garden Shed and The Sol system as our home.
We could use this term also for travelling to rogue planets, of which the Oort Cloud I would guess has many.
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The Sol Belt
The 'Asteroid Belt' closest to our star. The Kuiper Belt is an 'Asteroid Belt' calling the one closest to Sol is not a smart way to keep terms straight. We have two belts now.
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Dwarf Planet
A planet that orbits Sol, is rounded in appearance (over 90%) and is small. Usually the size of a moon.
Dwarf Moon
A moon that orbits a planet, is rounded in appearance (over 90%) and is small. Usually the size of a very large asteroid.
I suggest the criteria is:
1. it has at least percentile gravity (nothing can just 'float off' objects fall towards it)
2. regular orbit around it's parent.
3. is 90% or better rounded.
Failing to meet any these criteria would mean I would class it as an asteroid.
Moon
The above applies here also with the added criteria:
4. It must be able to sustain the orbit of a space vessel.
OR
4. It must have a core that is not merely regolith.
Planet
All of the above.
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The question has come up recently; what's a moon and what's not?
I based the above on the simple fact of what our moon is like; the most familiar and common denominator.
Moons should be 90%+ spherical. If its irregular.. it's an asteroid. Flip I would go so far as reclassifying Deimos and Phobos as asteroids. Yes they are Mars' asteroids, but still asteroids. Otherwise, maybe if they have a decent gravity and were spherical, they could be dwarf moons.
Which leads us nicely to..
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Asteroid Giants
I would suggest this is what Haumea is. Irregular shape but meeting the other criteria for a moon/dwarf planet.
We are looking for praiseworthy traits in our Solar 'worlds', the ability to spread gravity evenly via a sphere is praiseworthy, and while Hiʻiaka and Namaka, mean it would meet criteria 4, having what.. 60% sphericality? no I wouldn't be to hasty with the praise of 'dwarf planet'.
Ceres is a dwarf planet, Pluto is a dwarf planet.. Eris might be..80% to 90% spherical.. Haumea is an Asteroid Giant; call a spade a spade and have done with it :)
Asteroid
Simple chunk of rock in any shape except spherical. no 'core'. Just some rock, with or without a parent to orbit.
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