Sounds like a sleeping bag carried on the back (8)
I believe the answer is:
knapsack
'carried on the back' is the definition.
I can't tell whether this definition defines the answer.
'sounds like a sleeping bag' is the wordplay.
'sounds like' indicates a 'sounds like' (homophone) clue.
'a sleeping' becomes 'nap' (nap is a kind of sleeping).
'bag' becomes 'sack' (both can mean a container).
'nap' sounds like 'knap'.
'knap'+'sack'='KNAPSACK'
Can you help me to learn more?
(Other definitions for knapsack that I've seen before include "Bag with straps" , "Bag carried on back or shoulder" , "Traveller's or soldier's bag" , "Hiking bag" , "Hiker's bag" .)