Circulate butter, say (6)
I believe the answer is:
spread
This clue could be a double definition.
'circulate' is the first definition.
(synonyms)
'butter say' is the second definition.
'spread' can be an answer for 'butter' (thesaurus). I am not certain of the 'say' bit.
Can you help me to learn more?
(Other definitions for spread that I've seen before include "American farm" , "expansion?" , "See 4" , "Disseminate through padres" , "Scatter around" .)