Everyone in short dash for US city (6)
I believe the answer is:
dallas
'us city' is the definition.
(I've seen this before)
'everyone in short dash' is the wordplay.
'everyone' becomes 'all' (I've seen this before).
'in' means one lot of letters goes inside another.
'short' means to remove the last letter.
'dash' with its last letter taken away is 'das'.
'all' put inside 'das' is 'DALLAS'.
'for' acts as a link.
(Other definitions for dallas that I've seen before include "City in Texas; TV series" , "city built on oil" , "assassination site" , "Texan commercial city" , "Texas city where JFK was killed" .)