High ground cleft by rushing stream? (7)
I believe the answer is:
torrent
'rushing stream?' is the definition.
(I've seen this before)
'high ground cleft by' is the wordplay.
'high ground' becomes 'tor'.
'cleft' becomes 'rent' (synonyms).
'by' is a charade indicator (letters next to each other).
'tor'+'rent'='TORRENT'
(Other definitions for torrent that I've seen before include "Inundation" , "Violently fast stream of water" , "Raging flow" , "Fast-moving stream" , "Turbulent, swift-flowing stream" .)