touch on/upon
phrasal verb
touched on/upon;
touching on/upon;
touches on/upon
Definition of touch on/upon
1
: to briefly talk or write about (something) : to mention (something) briefly
The reports touched on many important points. She touches upon the issue in the article but never fully explains it.
2
: to come close to (something) : to almost be (something)
Her actions touched on treason.