It's said to raise a smile (6)
I believe the answer is:
cheese
'raise a smile' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'it's said' is the wordplay.
I cannot quite understand how this works, but
'it's' could be 'es' ('e' can mean 'electronic' which is similar to 'IT') and 'es' is present in the answer.
This may be the basis of clue (or it may be nonsense).
'to' acts as a link.
Can you help me to learn more?
(Other definitions for cheese that I've seen before include "Nautical cap worn without badge" , "Eg, cheddar" , "Red Leicester" , "See 22" , "E.g. brie" .)