Garment for artillery chief (4,3)
I believe the answer is:
tank top
'garment' is the definition.
(I've seen this before)
'artillery chief' is the wordplay.
'artillery' becomes 'tank' (I am not sure about this - if you are sure you should believe this answer much more).
'chief' becomes 'top' (synonyms).
'tank'+'top'='TANK TOP'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for tank top that I've seen before include "Close-fitting garment" , "piece of clothing" , "Upper body garment" , "Woollen sleeveless jumper" , "Young woman might appear in this" .)