Came in, redesigned small venues (7)
I believe the answer is:
cinemas
'venues' is the definition.
Although both the answer and definition are plural nouns, I can't see how they can define each other.
'came in redesigned small' is the wordplay.
'redesigned' indicates anagramming the letters.
'small' becomes 's' (abbreviation - e.g. clothes size).
'came'+'in'='camein'
'camein' with letters rearranged gives 'cinema'.
'cinema'+'s'='CINEMAS'
Can you help me to learn more?
(Other definitions for cinemas that I've seen before include "Picture-houses" , "Where films are shown" .)