Run off romantically (5)
I believe the answer is:
elope
'run off romantically' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for elope that I've seen before include "Run away to Gretna Green?" , "(Lovers) run away" , "Bolt" , "Run away to wed" , "Flee to wed" .)