Invert bobbin to produce twists (5)
I believe the answer is:
loops
'twists' is the definition.
(I've seen this before)
'invert bobbin' is the wordplay.
'invert' says the letters should be written in reverse.
'bobbin' becomes 'spool' (synonyms).
'spool' written backwards gives 'LOOPS'.
'to produce' is the link.
(Other definitions for loops that I've seen before include "Oval-shaped single coils, in a piece of thread perhaps" , "Twists" , "Winds" .)