Function without numerous turns of generator (6)
I believe the answer is:
dynamo
'generator' is the definition.
(I know that dynamo is a type of generator)
'function without numerous turns' is the wordplay.
'function' becomes 'do' (both can mean an event).
'without' indicates putting letters inside ('without' can be similar in meaning to 'outside').
'numerous' becomes 'many' (similar in meaning).
'turns' shows that the letters should be reversed in order.
'many' back-to-front is 'ynam'.
'do' going around 'ynam' is 'DYNAMO'.
'of' is the link.
(Other definitions for dynamo that I've seen before include "Source of electric current" , "Electricity generator: all-action type" , "Energetic person (colloq.)" , "Small generator" , "Generator (sometimes 'human'?)" .)