Crush page inside old papers (7)
I believe the answer is:
oppress
'crush' is the definition.
('oppress' can be a synonym of 'crush')
'page inside old papers' is the wordplay.
'page' becomes 'p'.
'inside' indicates putting letters inside.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'papers' becomes 'press' (I've seen this before).
'o'+'press'='opress'
'p' going into 'opress' is 'OPPRESS'.
(Other definitions for oppress that I've seen before include "Govern with cruelty and injustice" , "Treat harshly" , "Be brutal to" , "Treat cruelly" , "Govern cruelly" .)