Section of regiment old officer reprimanded (4,3)
I believe the answer is:
told off
'reprimanded' is the definition.
(telling off is a kind of reprimanding)
'section of regiment old officer' is the wordplay.
'section of' says the answer is hidden in the clue.
'TOLD OFF' is hidden in the letters of 'regiment old officer'.
(Other definitions for told off that I've seen before include "Rebuked" , "carpeting?" .)