Au (Noun)
Meaning 1
A soft yellow malleable ductile (trivalent and univalent) metallic element; occurs mainly as nuggets in rocks and alluvial deposits; does not react with most chemicals but is attacked by chlorine and aqua regia.
Classification
Nouns denoting substances.
Examples
- Gold, a chemical element with the symbol Au, is highly valued for its rarity, durability, and versatility.
- The chemical symbol for gold is Au, which comes from the Latin word for gold, aurum.
- In the periodic table, Au is the symbol for gold, a transition metal that is highly prized for its properties.
- The element Au is a good conductor of electricity and is often used in electronics and other applications.
- Au is a highly ductile metal, meaning it can be easily molded and shaped into various forms.
Synonyms
Hypernyms
Hyponyms
Meaning 2
A unit of length used for distances within the solar system; equal to the mean distance between the Earth and the Sun (approximately 93 million miles or 150 million kilometers).
Classification
Nouns denoting quantities and units of measure.
Examples
- The distance between the Earth and the Sun is approximately 1 au, which is a fundamental unit of measurement in astronomy.
- Astronomers often use the au as a convenient unit to express the vast distances between celestial bodies within the solar system.
- The mean distance between Mars and the Sun is about 1.38 au, which affects the planet's temperature and climate.
- To calculate the orbits of comets and asteroids, astronomers use the au as a standard unit of length for their complex mathematical models.
- The Kuiper Belt, a region of icy bodies beyond Neptune, stretches from about 30 to 55 au from the Sun, containing many small, frozen worlds.