Suggestion — request to refuse a drink (6)
I believe the answer is:
tipple
'drink' is the definition.
(I know that tipple is a type of drink)
'suggestion request to refuse a' is the wordplay.
I cannot quite understand how this works, but
'suggestion' could be 'tip' (tip is a kind of suggestion) and 'tip' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for tipple that I've seen before include "Imbibe" , "Alcoholic liquor" , "Drink (a little but often)" , "One's usual drink?" , "(Regular) alcoholic drink" .)