ADJ.
involved
SENATORIAL + NOUN
districts, investigation, subpoenas
adj
Relating to a senator.
Relating to a senate.
The senatorial investigation involved subpoenas and testimony before Congress and, of course, went nowhere.
Entitled to elect a senator, or by senators.
the senatorial districts of a State
i Register
In some senses, senatorial is marked as US. Watch for register when choosing this word.