Friend takes a minute with old soldier making retreat (5)
I believe the answer is:
amigo
'friend' is the definition.
(I've seen this before)
'a minute with old soldier making retreat' is the wordplay.
'minute' becomes 'm' (abbreviation).
'with' means one lot of letters go next to another.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'soldier' becomes 'gi' (GI can mean a US soldier).
'making retreat' says the letters should be written backwards (to retreat is to go backwards).
'o'+'gi'='ogi'
'ogi' reversed gives 'igo'.
'a'+'m'+'igo'='AMIGO'
'takes' acts as a link.
(Other definitions for amigo that I've seen before include "friend abroad" , "Mexican's mate" , "Friend in Spanish-speaking areas" , "Pal from Madrid?" , "Hispanic comrade" .)