Toboggan has new thrust (5)
I believe the answer is:
lunge
'thrust' is the definition.
(I know that lunge is a type of thrust)
'toboggan has new' is the wordplay.
'toboggan' becomes 'luge' (synonyms).
'has' is an insertion indicator.
'new' becomes 'n' (abbreviation as in New Testament NT).
'luge' placed around 'n' is 'LUNGE'.
(Other definitions for lunge that I've seen before include "Sudden forward movement" , "Impulsive move" , "Sudden forward move" , "Charge" , "Fall upon" .)