of or pertaining to rain, especially much rain; rainy.
2.
Geology. occurring through the action of rain.
noun
3.
Geology. a rainy period formerly regarded as coeval with a glacial age, but now recognized as episodic and, in the tropics, as characteristic of interglacial ages.
Origin: 1650–60; < Latinpluviālis, equivalent to pluvi(a) rain + -ālis-al1
1656, "pertaining to rain," from Fr. pluvial (12c.), from L. pluvialis "pertaining to rain," from (aqua) pluvia "rain (water)," from fem. of pluvius "rainy," from plovere "to rain," from PIE base *pleu- "to flow, to swim" (cf. Skt. plavate "navigates, swims;" Gk. plynein "to wash," plein "to navigate;"