Plan to zap each unfinished city square (5)
I believe the answer is:
plaza
'square' is the definition.
(I know that square can be written as plaza)
'plan to zap each unfinished city' is the wordplay.
I cannot really see how this works, but
'city' could be 'la' (Los Angeles) and 'la' is found in the answer.
an anagram of 'zap' is 'pza' which is present in the remaining letters.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for plaza that I've seen before include "Public square or market" , "Sp. square, market-place" , "Hotel" , "Open urban square or public area" , "Shopping mall" .)