Specially adapted troops shadowed guards (8)
I believe the answer is:
tailored
'specially adapted' is the definition.
'troops shadowed guards' is the wordplay.
'troops' becomes 'or' (military abbreviation for other ranks).
'shadowed' becomes 'tailed' (tailing is a kind of shadowing).
'guards' means one lot of letters goes inside another.
'or' going into 'tailed' is 'TAILORED'.
(Other definitions for tailored that I've seen before include "Cut to fit" , "Made to measure for idolater" , "cut to size" , "made-to-order" , "Suited to an individual" .)