Desperately got bag on sledge (8)
I believe the answer is:
toboggan
'sledge' is the definition.
(toboggan is a kind of sledge)
'desperately got bag on' is the wordplay.
'desperately' is an anagram indicator.
'got'+'bag'+'on'='gotbagon'
'gotbagon' anagrammed gives 'TOBOGGAN'.
(Other definitions for toboggan that I've seen before include "Sliding vehicle" , "Narrow sledge" , "Long narrow sled" , "Slider" , "Sled for sliding on snow" .)