New editor away drinking rum, went to sleep (6,3)
I believe the answer is:
nodded off
'went to sleep' is the definition.
('nod off' can be a synonym of 'go to sleep')
'new editor away drinking rum' is the wordplay.
'new' becomes 'n'.
'editor' becomes 'ed'.
'away' becomes 'off' ('off' can be a synonym of 'away'**).
'drinking' indicates putting letters inside.
'rum' becomes 'odd' (I've seen this before).
'n'+'ed'+'off'='nedoff'
'nedoff' placed around 'odd' is 'NODDED OFF'.
(Other definitions for nodded off that I've seen before include "Fell asleep" , "dozed" .)