Knock-out verse about Irish city (5)
I believe the answer is:
kirov
'city' is the definition.
(I have seen 'Russian city' mean 'kirov' so perhaps 'city' could also mean 'kirov')
'knock-out verse about irish' is the wordplay.
'knock out' becomes 'ko'.
'verse' becomes 'v'.
'about' indicates putting letters inside.
'irish' becomes 'IR' (abbreviation).
'ko'+'v'='kov'
'kov' going around 'ir' is 'KIROV'.
(Other definitions for kirov that I've seen before include "Sergei -, Communist assassinated 1934" , "Stalinist" , "Soviet city" , "Russian city and ballet company" , "Soviet ballet" .)