Complete brigade moved into a French stronghold at last (10)
I believe the answer is:
unabridged
'complete' is the definition.
(similar in meaning)
'brigade moved into a french stronghold at last' is the wordplay.
'moved' indicates an anagram.
'into' indicates putting letters inside.
'a french' becomes 'un' ('a' in French).
'at last' says to take the final letters.
The final letter of 'stronghold' is 'd'.
'brigade' with letters rearranged gives 'abridge'.
'un'+'d'='und'
'abridge' going within 'und' is 'UNABRIDGED'.
(Other definitions for unabridged that I've seen before include "published in full" , "Not shortened" , "Complete" .)