A girl got out of bed (5)
I believe the answer is:
arose
'got out of bed' is the definition.
(I've seen this in another clue)
'a girl' is the wordplay.
'girl' becomes 'rose' ().
'a'+'rose'='AROSE'
(Other definitions for arose that I've seen before include "Cropped up" , "Happened" , "Sprang up" , "Emerged from" , "Occurred; stood up" .)