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Definition

noun

1. (chemistry) a chemical substance, with chemical formula H₂O, that is clear, colorless, oderless, and tasteless liquid that may also occur in various forms such as gas (water vapour) and solid (ice).

Water is regarded as the universal solvent primarily due to its chemical and physical properties. It is one of the substances essential to life. Biomolecules (DNA, proteins, polysaccharides, etc.) are dissolved in water. It is also one of the requirements for photosynthesis. Some of its properties are described as follows:

• Water is a tasteless, odorless liquid at ambient temperature and pressure.
• Water is transparent, making it possible for aquatic plants to live in since sunlight can penetrate through.
• Water is a liquid under standard conditions.
• Water is polar molecule due to its oxygen that has a slight negative charge while its hydrogens have slight positive charge.
• Water molecules stick to one another by hydrogen bond.
• Water has high surface tension. It is essential to yield elasticity that drives the capillary waves.
• Water has high adhesion properties.
• Water has the ability for capillary action, the tendency to move up a narrow tube against gravity, a property relied upon by vascular plants, such as trees.
• Water has the second highest specific heat capacity (after ammonia) and high heat of vaporization. These properties allow water to regulate the Earth’s climate.
• Water is less dense upon freezing, causing the solidified water (ice) to float above the surface, making it possible for aqueous organisms to still live below or at the bottom.

2. (chemistry) an aqueous solution of a substance, for example ammonia water, waste water

3. a body of water, like sea, rivers and lakes, and a naturally-occurring water like mineral water

4. amniotic fluid, as in the pregnant woman’s water breaks

verb

1. to pour water; to make wet

2. to provide with water; to irrigate

3. to dilute

3. to discharge fluid; (colloquial) to urinate

4. to fill the eyes with tears

5. to salivate in anticipation of food

Word origin: From Old English wæter, from Proto-Germanic *wat-, from heteroclitic r/n-stem Proto-Indo-European *wódr̥ (genitive *wednós (“‘of water’”)). Cognates include German Wasser, Dutch water, Irish uisce, Russian вода (voda), Latin unda and Lithuanain vanduo.