Open English Wordnet
Nouns
(n)rain, rainfallwater falling in drops from vapor condensed in the atmosphere (n)rain, rainwaterdrops of fresh water that fall as precipitation from clouds (n)rain, peltinganything happening rapidly or in quick successive“a rain of bullets”,
“a pelting of insults” Verbs
(v)rain, rain downprecipitate as rain“If it rains much more, we can expect some flooding”