Partly built street reduced to ruins? (4)
I believe the answer is:
bust
'to ruins?' is the definition.
(I know that bust is a more specific form of the action destroy)
'partly built street reduced' is the wordplay.
'partly built' becomes 'bu' (I can't explain this - if you can you should believe this answer much more).
'street reduced' becomes 'st' (abbreviation; 'reduced' asks for an abbreviation).
'bu'+'st'='BUST'
Can you help me to learn more?
(Other definitions for bust that I've seen before include "economic collapse" , "reduced to rubble?" , "Sculpture of head and chest" , "Sculptor's piece" , "Broke (Sl.)" .)