Casino's refurbished after over 100 functions (9)
I believe the answer is:
occasions
'functions' is the definition.
(I know this)
'casino's refurbished after over 100' is the wordplay.
'refurbished' indicates an anagram.
'after' means one lot of letters go next to another.
'over' becomes 'o' (cricket abbreviation).
'100' becomes 'C' (Roman numeral).
'casinos' is an anagram of 'casions'.
'o'+'c'='oc'
'casions' put after 'oc' is 'OCCASIONS'.
(Other definitions for occasions that I've seen before include "Celebrations" , "Special times or events" , "Causes to happen" , "Social events" .)