Banish cross page occupying overturned shelter (5)
I believe the answer is:
expel
'banish' is the definition.
(I've seen this before)
'cross page occupying overturned shelter' is the wordplay.
'cross' becomes 'x' (an X is a cross).
'page' becomes 'p'.
'occupying' is an insertion indicator (inserted letters occupy or enter the word).
'overturned' is a reversal indicator.
'shelter' becomes 'lee' (as in lee side, the side sheltered from wind).
'lee' in reverse letter order is 'eel'.
'x'+'p'='xp'
'xp' placed within 'eel' is 'EXPEL'.
(Other definitions for expel that I've seen before include "Possibly remove from club" , "Evict" , "Banish (undesirable alien?)" , "Remove from membership" , "Drive out with force" .)