Out of context, rather more (5)
I believe the answer is:
extra
'more' is the definition.
(I've seen this before)
'out of context rather' is the wordplay.
'out of' indicates a hidden word.
'EXTRA' is hidden within 'context rather'.
(Other definitions for extra that I've seen before include "Surcharge" , "Spare" , "There's more" , "wide? It could be" , "bit-part player" .)