Definify.com

Webster 1913 Edition

Adj.

Falling copiously or in streams, as from a sluice.

And oft whole sheets descend of

sluicy

rain.

Dryden.

,SLU'SY,

Adj.

Falling in streams as from a sluice. And oft whole sheets descent of sluicy rain.

sluicy ‎(comparative more sluicy, superlative most sluicy)

Falling copiously or in streams, as if from a sluice.
- John Dryden
  And oft whole sheets descend of sluicy rain.