Crash into some wall (7)
I believe the answer is:
rampart
'wall' is the definition.
(I know that wall can be written as rampart)
'crash into some' is the wordplay.
'crash into' becomes 'ram' (I've seen this before).
'some' becomes 'part' (only part of something).
'ram'+'part'='RAMPART'
(Other definitions for rampart that I've seen before include "Fortified wall" , "Bulwark, wall" , "section of defence?" , "defencework" , "Pain-relieving drug" .)