Crossword Genius

Situation for highest-level worker? (7)

Ross

I believe the answer is:

rooftop

But I can't explain it at all!

(Other definitions for rooftop that I've seen before include "Highest point of dwelling" , "Minimum height for low flying" , "Building's highest point" , "High point of building (from which to shout?)" , "Building's upper surface" .)

I've seen this clue in The Times.
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