Changes

==Etymology==

==Etymology==

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English], from [https://nordan.daynal.org/wiki/index.php?title=English#ca._600-1100.09THE_OLD_ENGLISH.2C_OR_ANGLO-SAXON_PERIOD Old English] wæter; akin to Old High German wazzar water, [[Greek]] hydōr, [[Latin]] unda  [[wave]]

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English], from [https://nordan.daynal.org/wiki/index.php?title=English#ca._600-1100.09THE_OLD_ENGLISH.2C_OR_ANGLO-SAXON_PERIOD Old English] wæter; akin to Old High German wazzar water, [[Greek]] hydōr, [[Latin]] unda  [[wave]]

*Date: before [http://www.wikipedia.org/wiki/12th_Century 12th century]

*Date: before [https://www.wikipedia.org/wiki/12th_Century 12th century]

==Definitions==

==Definitions==

*1 a : the [[liquid]] that [[descends]] from the clouds as rain, [[forms]] streams, lakes, and seas, and is a major constituent of all living [[matter]] and that when [[pure]] is an odorless, tasteless, very slightly compressible liquid oxide of hydrogen H2O which appears bluish in thick layers, freezes at 0° C and boils at 100° C, has a maximum [[density]] at 4° C and a high specific [[heat]], is feebly ionized to hydrogen and hydroxyl [[ions]], and is a poor conductor of [[electricity]] and a good [[solvent]]  

*1 a : the [[liquid]] that [[descends]] from the clouds as rain, [[forms]] streams, lakes, and seas, and is a major constituent of all living [[matter]] and that when [[pure]] is an odorless, tasteless, very slightly compressible liquid oxide of hydrogen H2O which appears bluish in thick layers, freezes at 0° C and boils at 100° C, has a maximum [[density]] at 4° C and a high specific [[heat]], is feebly ionized to hydrogen and hydroxyl [[ions]], and is a poor conductor of [[electricity]] and a good [[solvent]]  

:b : fictitious or exaggerated [[asset]] entries that give a stock an unrealistic book [[value]]

:b : fictitious or exaggerated [[asset]] entries that give a stock an unrealistic book [[value]]

==Description==

==Description==

[[Water]] is a [[chemical]] substance that is [[composed]] of [http://en.wikipedia.org/wiki/Hydrogen hydrogen] and [http://en.wikipedia.org/wiki/Oxygen oxygen] and is vital for all known [[forms]] of life.

[[Water]] is a [[chemical]] substance that is [[composed]] of [https://en.wikipedia.org/wiki/Hydrogen hydrogen] and [https://en.wikipedia.org/wiki/Oxygen oxygen] and is vital for all known [[forms]] of life.

In typical usage, water refers only to its [[liquid]] [[form]] or state, but the substance also has a [[solid]] state, ice, and a [[gaseous]] state, [http://en.wikipedia.org/wiki/Water_vapor water vapor] or [http://en.wikipedia.org/wiki/Steam steam]. Water covers 71% of the [[Earth]]'s [[surface]]. On [[Earth]], it is found mostly in [[oceans]] and other large water bodies, with 1.6% of water below ground in [http://en.wikipedia.org/wiki/Aquifer aquifers] and 0.001% in the air as [http://en.wikipedia.org/wiki/Vapor vapor], [http://en.wikipedia.org/wiki/Cloud clouds] (formed of solid and liquid water [[particles]] suspended in air), and [http://en.wikipedia.org/wiki/Precipitation_(meteorology) precipitation]. Oceans hold 97% of [[surface]] water, [http://en.wikipedia.org/wiki/Glacier glaciers] and polar [http://en.wikipedia.org/wiki/Ice_cap ice caps] 2.4%, and other land surface water such as rivers, lakes and ponds 0.6%. A very small amount of the [[Earth]]'s water is contained within [[biological]] [[bodies]] and manufactured products.

In typical usage, water refers only to its [[liquid]] [[form]] or state, but the substance also has a [[solid]] state, ice, and a [[gaseous]] state, [https://en.wikipedia.org/wiki/Water_vapor water vapor] or [https://en.wikipedia.org/wiki/Steam steam]. Water covers 71% of the [[Earth]]'s [[surface]]. On [[Earth]], it is found mostly in [[oceans]] and other large water bodies, with 1.6% of water below ground in [https://en.wikipedia.org/wiki/Aquifer aquifers] and 0.001% in the air as [https://en.wikipedia.org/wiki/Vapor vapor], [https://en.wikipedia.org/wiki/Cloud clouds] (formed of solid and liquid water [[particles]] suspended in air), and [https://en.wikipedia.org/wiki/Precipitation_(meteorology) precipitation]. Oceans hold 97% of [[surface]] water, [https://en.wikipedia.org/wiki/Glacier glaciers] and polar [https://en.wikipedia.org/wiki/Ice_cap ice caps] 2.4%, and other land surface water such as rivers, lakes and ponds 0.6%. A very small amount of the [[Earth]]'s water is contained within [[biological]] [[bodies]] and manufactured products.

Water on [[Earth]] moves [[continually]] through a [[cycle]] of [http://en.wikipedia.org/wiki/Evaporation evaporation] or [http://en.wikipedia.org/wiki/Transpiration transpiration] (evapotranspiration), [http://en.wikipedia.org/wiki/Precipitation_(meteorology) precipitation], and runoff, usually reaching the sea. Over land, evaporation and transpiration [[contribute]] to the precipitation over land.

Water on [[Earth]] moves [[continually]] through a [[cycle]] of [https://en.wikipedia.org/wiki/Evaporation evaporation] or [https://en.wikipedia.org/wiki/Transpiration transpiration] (evapotranspiration), [https://en.wikipedia.org/wiki/Precipitation_(meteorology) precipitation], and runoff, usually reaching the sea. Over land, evaporation and transpiration [[contribute]] to the precipitation over land.

Clean [http://en.wikipedia.org/wiki/Drinking_water drinking water] is [[essential]] to [[human]] and other lifeforms. Access to safe drinking water has improved steadily and substantially over the last decades in almost every part of the world. There is a clear correlation between access to safe water and [http://en.wikipedia.org/wiki/Gross_domestic_product GDP] per capita. However, some [[observers]] have estimated that by 2025 more than half of the world [[population]] will be facing water-based vulnerability. A recent report (November 2009) suggests that by 2030, in some developing regions of the world, water demand will exceed supply by 50%. Water plays an important role in the world economy, as it [[functions]] as a [[solvent]] for a wide variety of [[chemical]] substances and [[facilitates]] industrial cooling and [[transportation]]. Approximately 70% of [http://en.wikipedia.org/wiki/Freshwater freshwater] is consumed by agriculture.[http://en.wikipedia.org/wiki/Water]

Clean [https://en.wikipedia.org/wiki/Drinking_water drinking water] is [[essential]] to [[human]] and other lifeforms. Access to safe drinking water has improved steadily and substantially over the last decades in almost every part of the world. There is a clear correlation between access to safe water and [https://en.wikipedia.org/wiki/Gross_domestic_product GDP] per capita. However, some [[observers]] have estimated that by 2025 more than half of the world [[population]] will be facing water-based vulnerability. A recent report (November 2009) suggests that by 2030, in some developing regions of the world, water demand will exceed supply by 50%. Water plays an important role in the world economy, as it [[functions]] as a [[solvent]] for a wide variety of [[chemical]] substances and [[facilitates]] industrial cooling and [[transportation]]. Approximately 70% of [https://en.wikipedia.org/wiki/Freshwater freshwater] is consumed by agriculture.[https://en.wikipedia.org/wiki/Water]

[[Category: Chemistry]]

[[Category: Chemistry]]

[[Category: Earth Science]]

[[Category: Earth Science]]