British soldier on flipping hill? Nonsense (8)
I believe the answer is:
tommyrot
'nonsense' is the definition.
(I know that tommyrot is a type of nonsense)
'british soldier on flipping hill?' is the wordplay.
'british soldier' becomes 'tommy' (I've seen this before).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'flipping' is a reversal indicator.
'hill?' becomes 'tor' (tor is a kind of hill).
'tor' back-to-front is 'rot'.
'tommy'+'rot'='TOMMYROT'
(Other definitions for tommyrot that I've seen before include "Nonsense, rubbish - ask informal Thomas" , "Slangy nonsense from Thomas?" , "Absolute rubbish, nonsense" , "tosh" , "Balderdash, bilge" .)