I have proven, your descriptions are not words.
You have proven no such thing.
By your own admission they are words, specifically jargon:
"special words or expressions used by a profession or group that are difficult for others to understand."
That means it isn't real
The existence and acceptance of a word has no bearing upon if what it describes is real.
This means Earth can have no gas, a layer of gas above an open surface, or a shell of gas around a closed surface.
As such, your semantics has absolutely no bearing upon if Earth is flat.
Expressions. Meaning "a word or phrase, especially an idiomatic one, used to convey an idea." This does not make it a word. It makes it a fancy form of slang. Its no different then me saying "I got ganked on Charlie by a tank with a healer." Means nothing... Outside the gaming community. Its meaningless without context. However, this is not the case with actual words. Uaing recognised words, i can convey a thought without the necessary "in knowledge" of a particular group. IE: yeah, I ran into this guy who won without a fight from me. He ambushed me, and all the damage I did was negated by his friend healing him during the fight (I got ganked on Charlie by a tank and his healer).
As for your second thought... That makes 0 sense. The Earth has an atmosphere. Detailed by science, defined by dictionaries, breathed by us. The Earth, by definition, has to be round, with a gaseous layer. Atmodisk isn't a word. Atmo... What else? Layer? Plane? Whatever it was... Also isn't a word. At best it is jargon, which is acceptable, and really only understood, within a particular group, and at worst is just nonsense slang understood only within a particular group. (See what i did there? It wasn't by accident).
"However, if you still insist on using jargon, and I can't change your mind, then I can end this whole debate really quick (since apparently you need to use jargon, AND declare yourself the winner amongst Flat Earthers). Ahem. You're entire argument is Hardline. I'm right. You re wrong. End of discussion
There. Now we have settled that. You're more then welcome to join me in the victor's sphere."
Do you see how silly the whole section in quotes sounds? Using jargon never amounts to anything. So, show me, in a dictionary of record, atmo[indication of flat here]. Let me see Miriam Webster, or the Oxford Dictionary showing it. Even better, show me proof that cannot be debunked. Come up with the NASA secret plans. I'm open minded. I really am. However, no Flat Earther has ever impressed me, and most come across as egotistical, and/or unable to cope with the thought that they aren't special. They are like every one else. You are a scientist? Fine. Show me undeniable proof.