Old person says 'rain dances' (8)
I believe the answer is:
assyrian
'old person' is the definition.
(person from ancient Assyria)
'says rain dances' is the wordplay.
'dances' indicates an anagram.
'says'+'rain'='saysrain'
'saysrain' is an anagram of 'ASSYRIAN'.
(Other definitions for assyrian that I've seen before include "one in Iraq once" , "race" , "Old middle eastern type" , "Extinct language" , "ancient language" .)