Worshipping a barbaric rain god (7)
I believe the answer is:
adoring
'worshipping' is the definition.
(I've seen this before)
'a barbaric rain god' is the wordplay.
'a barbaric' indicates an anagram (a rough or barbaric form of the letters).
'rain'+'god'='raingod'
'raingod' with letters rearranged gives 'ADORING'.
(Other definitions for adoring that I've seen before include "Devoted" , "Worshipping; admiring" , "Holding dear" , "Showing great affection" , "Worshipping the loved one" .)