Sailor goes to the edge completely full (5)
I believe the answer is:
abrim
'completely full' is the definition.
(I've seen this before)
'sailor goes to the edge' is the wordplay.
'sailor' becomes 'ab' (abbreviation for able seaman).
'goes to' says to put letters next to each other.
'the edge' becomes 'rim' (rim is a kind of edge).
'ab'+'rim'='ABRIM'
(Other definitions for abrim that I've seen before include "Spilling over" , "Completely full" .)