Sneaked (5)
I believe the answer is:
crept
'sneaked' is the definition.
('creep' can be a synonym of 'sneak')
This is the entire clue.
(Other definitions for crept that I've seen before include "Went stealthily or furtively" , "was obsequious" , "acted in subservient way" , "Moved slowly and carefully" , "Sneaked" .)