Added 9 October 2026 rainstorm /ˈɹeɪnstɔːm/ noun Categories: NatureRare Words noun ! Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about rainstorm at Wordnik → Where our words come from → A storm with rain. Origin From rain + storm. From Wiktionary, via Kaikki.org (CC BY-SA) Related Words: thundershowerrainfallraintempestdownpourrainystormthunderstormrainforestheavyrainpourraining Back to today's word