Arrest idiot holding minute navigational aid (7)
I believe the answer is:
compass
'navigational aid' is the definition.
(I've seen this before)
'arrest idiot holding minute' is the wordplay.
'arrest' becomes 'cop' ('cop' can be a synonym of 'arrest').
'idiot' becomes 'ass' (I've seen this before**).
'holding' indicates putting letters inside.
'minute' becomes 'm' (abbreviation).
'cop'+'ass'='copass'
'copass' going around 'm' is 'COMPASS'.
(Other definitions for compass that I've seen before include "where all points considered?" , "Box the ---, change fully round" , "Course guide" , "Achieve" , "Device with magnetic needle for determining direction" .)