thorny
US /ˈθɔːr.ni/
UK /ˈθɔːr.ni/

1.
2.
spinoso, difficile, complicato
causing difficulties or disagreements; complex and difficult to deal with
:
•
The negotiations faced many thorny issues.
I negoziati hanno affrontato molte questioni spinose.
•
It was a thorny problem that required careful consideration.
Era un problema spinoso che richiedeva un'attenta considerazione.