Tongue endlessly manoeuvring round a sweet (6)
I believe the answer is:
nougat
'sweet' is the definition.
(nougat is a kind of sweet)
'tongue endlessly manoeuvring round a' is the wordplay.
'endlessly' means to remove the last letter.
'manoeuvring' indicates an anagram.
'round' means one lot of letters goes inside another.
'tongue' with its last letter taken away is 'tongu'.
'tongu' anagrammed gives 'nougt'.
'nougt' going around 'a' is 'NOUGAT'.
(Other definitions for nougat that I've seen before include "Sweet made from honey, egg white and nuts" , "Honey/nuts sweet" , "Chewy sweetmeat" , "Chewy sweets made of nuts, sugar and albumen" , "Oat gun for a sweet" .)