The most common and most likely answer to this crossword clue is the 6 letter word TURRET
I've seen this crossword clue in Financial Times
T
U
R
R
E
T
More clues leading to the result TURRET
- Time-keeper raised Trade Union rights and so on: impasse
- Tower‘s shaky, utter rubbish top
- Surrey without a fringe kept in dry tower
- Rebellious blighter ruthlessly guarding gun enclosure
- Feature of tank tops in tailor’s, unusually retro, raised eyebrows there
- Expression of disapproval about upsetting sin — guns out of here?
- Utter nonsense about king in tower
- Revolving structure kept by fighter ruthlessly in revolution
- Utter reconstruction around royal tower
Buddy explains!

The straight part
We know that "tower" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tower = turret.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TURRET mean?
TURRET noun- A little tower, frequently a merely ornamental structure at one of the corners of a building or castle.
- A siege tower; a movable building, of a square form, consisting of ten or even twenty stories and sometimes one hundred and twenty cubits high, usually moved on wheels, and employed in approaching a fortified place, for carrying soldiers, engines, ladders, casting bridges, and other necessaries.
- A tower-like solder post on a turret board (a circuit board with posts instead of holes).
- An armoured, rotating gun installation on a fort, ship, aircraft, or armoured fighting vehicle.
- The elevated central portion of the roof of a passenger car, with sides that are pierced for light and ventilation.