Initially carried away in a box (6)
I believe the answer is:
coffin
'a box' is the definition.
(coffin is a kind of box)
'initially carried away in' is the wordplay.
'initially' says to take the initial letters.
'away' becomes 'off' ('off' can be a synonym of 'away'**).
The initial letter of 'carried' is 'c'.
'c'+'off'+'in'='COFFIN'
(Other definitions for coffin that I've seen before include "Corpse's chest" , "Sarcophagus" , "Body box" , "Casket for a corpse" , "Box for a corpse" .)