Drag spare tyre over (3)
I believe the answer is:
tug
'drag' is the definition.
(thesaurus)
'spare tyre over' is the wordplay.
'spare tyre' becomes 'gut' ('spare tyre' can refer to fat around the waist).
'over' says the letters should be written backwards.
'gut' in reverse letter order is 'TUG'.
(Other definitions for tug that I've seen before include "Powerful boat" , "Boat to pull larger one" , "Pull sharply" , "Small ship for pulling" , "Pull forcibly" .)