Egypt divider (4)
I believe the answer is:
nile
'egypt divider' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for nile that I've seen before include "World's longest river" , "'The longest river, blue and white (4)'" , "Cleopatra's river" , "River of eastern Africa" , "Current" .)