Sweet pea still out (8)
I believe the answer is:
pastille
'sweet' is the definition.
(pastille is a kind of sweet)
'pea still out' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'pea'+'still'='peastill'
'peastill' anagrammed gives 'PASTILLE'.
(Other definitions for pastille that I've seen before include "drop" , "Lozenge, to soothe the throat perhaps" , "Cough lozenge" , "Flavoured sweet for sucking" , "Small, often medicated, sweet" .)