When using plugins and commercial themes in WordPress, it’s not uncommon to meet code like this:
[one_half] [service_box] <h1>Title:</h1> <ul> <li>blah...</li> <li>blah...</li> <li>blah...</li> </ul> [/service_box] [/one_half] [one_half_last] Something more irrelevant here [/one_half_last]
Does this thing have a name in the WordPress jargon?
I would use the phrase
to describe it.
You can find many questions using that phrase here on WPSE.
The Codex also uses it, for example here:
Since the shortcodes in your example are related to the layout, we could perhaps call it:
Nested Layout Shortcodes
to be more specific.
If you have another phrase in mind, or a better suggestion, please share it with us.