Afghan regularly seen as military commander (3)
I believe the answer is:
aga
'military commander' is the definition.
(I've seen this before)
'afghan regularly seen' is the wordplay.
'regularly seen' indicates alternate letters.
The alternate letters of 'afghan' are 'AGA'.
'as' is the link.
(Other definitions for aga that I've seen before include "Captain" , "Cooker" , "Muslim title and cooking stove" , "Turkish title and metal stove" , "... Khan is a spiritual Muslim leader" .)