In case you weren't already aware, most markdown parsers support actual HTML tags in it, and there's <abbr title="change data capture">CDC</abbr> that allows being visually succinct, is a11y friendly, and in most browsers is visually distinct to prompt the user there's more content hidden in the hover or long-press

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/ab...

I'm also aware of https://developer.mozilla.org/en-US/docs/Web/HTML/Element/df... but I think it has more nuance to it and for sure involves having a lot more supporting structure in the document