you could use the linkify macro to call the tiddler titled “TW”, and have it view the field “caption”
You can find it here, I replaced linkify() with !!() just so I don’t have to type as much, but that’s a matter of preference, you could change it to be <<$$ TW>>
As far as using &“TiddlerAbbriviation”&, you would have to make your own parsing wikitext(I think that is what it is called?) which isn’t something I’m sure how to do, it is something I am trying to currently learn as well.