nouns
a small waterfall or series of small waterfalls
is a type of (narrower)
a steep descent of the water of a river
a succession of stages or operations or processes or units
"progressing in severity as though a cascade of genetic damage was occurring"; "separation of isotopes by a cascade of processes"
is a type of (narrower)
a group of people or things arranged or following in order
"a succession of stalls offering soft drinks"; "a succession of failures"
a sudden downpour (as of tears or sparks etc) likened to a rain shower
"a little shower of rose petals"; "a sudden cascade of sparks"