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rainwater

1 American  
[reyn-waw-ter, -wot-er] / ˈreɪnˌwɔ tər, -ˌwɒt ər /

noun

  1. water fallen as rain.


Rainwater 2 American  
[reyn-waw-ter, -wot-er] / ˈreɪnˌwɔ tər, -ˌwɒt ər /

noun

  1. (Leo) James, 1917–86, U.S. physicist: Nobel Prize 1975.


rainwater British  
/ ˈreɪnˌwɔːtə /

noun

  1. water from rain (as distinguished from spring water, tap water, etc)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of rainwater

before 1000; Middle English rein water, Old English regn-wæter; rain, water

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Oil fires can also release sulphur and nitrogen oxides, which can form acids if they dissolve in rainwater, as well as other harmful hydrocarbons, metallic compounds and droplets of oil.

From BBC

On Earth, most sulfates dissolve easily in rainwater.

From Science Daily

Stroud Brewery is organic, so it does not use pesticides or herbicides, and uses harvested rainwater to flush its toilets.

From BBC

As of December, its dams were only around 30 percent full on average, and farmers have largely relied on rainwater for irrigation.

From Barron's

By examining their chemical makeup -- the balance between "heavy" and "light" hydrogen in the waxes mirrors the hydrogen composition of rainwater absorbed by plants -- the team was able to estimate the severity of drought conditions.

From Science Daily