Bikie's attachment to cocktail? (7)
I believe the answer is:
sidecar
'cocktail?' is the definition.
(I know that sidecar is a type of cocktail)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for sidecar that I've seen before include "Where a passenger may go" , "Cocktail; bike attachment" , "passenger compartment" , "Attachment on motorcycle to carry passenger" , "In which Gromit goes" .)