thorny
US /ˈθɔːr.ni/
UK /ˈθɔːr.ni/

1.
2.
espinhoso, complicado, difícil
causing difficulties or disagreements; complex and difficult to deal with
:
•
The negotiations faced many thorny issues.
As negociações enfrentaram muitas questões espinhosas.
•
It was a thorny problem that required careful consideration.
Era um problema espinhoso que exigia consideração cuidadosa.