Tear off about ten more (5)
I believe the answer is:
extra
'more' is the definition.
(I've seen this in other clues)
'tear off about ten' is the wordplay.
'off' indicates anagramming the letters.
'about' is an insertion indicator.
'ten' becomes 'X' (Roman numeral).
'tear' with letters rearranged gives 'etra'.
'etra' going around 'x' is 'EXTRA'.
(Other definitions for extra that I've seen before include "non-standard item" , "Additional expense" , "A bit on the side" , "Superfluous" , "One playing small part" .)