noun A (large) waterfall, specifically one flowing over the edge of a cliff.
The cataracts on the Nile helped to compartment Upper Egypt.
noun A flood of water; specifically, steep rapids in a river.
noun An overwhelming downpour or rush; a flood.
His cataract of eloquence
noun A type of governor used in single-acting steam engines, where a flow of water through an opening regulates the stroke.
noun Synonym of waterspout (“a whirlwind that forms over water”).
verb Of a river, etc.: to fall in the form of a waterfall.
verb To cause (something) to pour or rush like a waterfall.
noun Synonym of portcullis (“a gate in the form of a grating which is lowered into place at the gateway of a castle, a fort, etc.”); also, a window grating.