Second shelf has a toboggan (6)
I believe the answer is:
sledge
'a toboggan' is the definition.
(I've seen this before)
'second shelf' is the wordplay.
'second' becomes 's' (common abbreviation).
'shelf' becomes 'ledge' ('ledge' can be a synonym of 'shelf').
's'+'ledge'='SLEDGE'
'has' is the link.
(Other definitions for sledge that I've seen before include "Vehicle for travelling over snow" , "Snow vehicle or heavy hammer" , "Vehicle for use in snow" , "Vehicle for transportation over snow" , "Transport on snow - hammer" .)