25 across
Visitor
is
interrupting
perturbed
tutor
(7)
Visitor is interrupting perturbed tutor (7)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
The definition is Visitor — someone who tours. Take tutor and perturbed it (anagram it) to get TOURT, then let IS interrupt in the middle, giving you TOUR-IS-T.