Return of strange meeting (5)
I believe the answer is:
forum
'meeting' is the definition.
(I know that forum is a type of meeting)
'return of strange' is the wordplay.
'return' is a reversal indicator.
'strange' becomes 'rum' (synonyms).
'of' reversed gives 'fo'.
'fo'+'rum'='FORUM'
(Other definitions for forum that I've seen before include "place for debate" , "Tribunal" , "Arena for debate" , "discussion group" , "Medium for discussion" .)