This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

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adj. Of or relating to rain; rainy.

adj. Geology Marked or formed by abundant rainfall: pluvial periods; a pluvial lake.

n. Geology An extended period of abundant rainfall, especially such a period of the Pleistocene Epoch.

adj. Of, pertaining to, or produced by rain

adj. occurring through the action of rain

n. a rainy period

adj. Of or pertaining to rain; rainy.

adj. Produced by the action of rain.

n. A priest's cope.

Rainy; humid: relating to rain; also, very rainy; characterized by great or extensive rainfall

In geology, depending on or arising from the action of rain.

n. Eccles., a cope: so called from its use in outdoor processions, etc., as a protection from the weather.

"The northern parts of the hotspot in Ecuador and the Colombian Chocó are characterized by extremely wet or pluvial forests that receive eight meters of annual rainfall and have a diversity per hectare of as many as 300 tree species."

pluvial lake   

rainy   

alluvial    fluvial