Lamb almost returning with a silent sled dog (8)

'sled dog' is the definition.
(malamute is a kind of sled dog)

'lamb almost returning with a silent' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'returning' says the letters should be written backwards.
'with' says to put letters next to each other.
'silent' becomes 'mute' (synonyms).
'lamb' with its final letter taken away is 'lam'.
'lam' backwards is 'mal'.
'mal'+'a'+'mute'='MALAMUTE'