Additional troops posted in Maine (4)

I believe the answer is:

'additional' is the definition.
(synonyms)

'troops posted in maine' is the wordplay.
'troops' becomes 'or' (military abbreviation for other ranks).
'posted in' means one lot of letters goes inside another.
'maine' becomes 'me'.
'or' going within 'me' is 'MORE'.

(Other definitions for more that I've seen before include "See 9" , "A greater amount" , "Writer" , "victim of Henry" , "Greater quantity or number" .)

I've seen this clue in The Independent.

Want a hint initially instead of a full solution? Install my app