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The Complete Vocabulary Builder Workbook



How to pronounce equinox (audio)

Dictionary definition of equinox

An astronomical event that occurs twice a year when the sun is directly above the equator and the day and night are of approximately equal length.
"In the Southern Hemisphere, the vernal equinox marks the start of autumn."

Detailed meaning of equinox

"Equinox" is a noun that refers to either of two points on the celestial sphere where the celestial equator and the ecliptic intersect. The two points occur twice a year, around March 20th and September 22nd and mark the beginning of spring (Vernal Equinox) and fall (Autumnal Equinox) respectively.

At the equinox, the tilt of the Earth's axis is not inclined toward or away from the sun, and as a result, the amount of daylight and darkness is roughly equal all over the world. It is a significant event in the astronomical calendar and is used to mark the start of the seasons and to set the dates of the calendars.

During the Vernal Equinox, the sun is exactly above the equator, and the day and night are of equal duration all over the Earth. On the other hand, during the Autumnal Equinox, the sun is again exactly above the equator and the day and night are of equal duration.

In addition, the term "equinox" is also used to describe a state of balance or equality, such as a point in time or a situation where different factors are in equilibrium. For example, an economic equinox is a state of balance in the economy where supply and demand are in balance and prices are stable.

Overall, the equinox is an important astronomical event that marks the beginning of the seasons and denotes the balance or equality of daylight and darkness all over the world.

Example sentences containing equinox

1. The equinox marks the moment when day and night are of equal length.
2. People around the world celebrate the vernal equinox as the arrival of spring.
3. During the autumnal equinox, the Earth's axis is neither tilted toward nor away from the Sun.
4. The equinox is a significant event in many cultural and religious calendars.
5. Astronomers study the equinox to understand celestial phenomena.
6. The equinox occurs twice a year, in March and September.

History and etymology of equinox

The noun 'equinox' has its etymology rooted in Latin. It is derived from the Latin words 'aequus,' meaning 'equal,' and 'nox,' meaning 'night.' In Latin, 'aequinoctium' referred to the time of year when the day and night were of approximately equal length, marking the two points in the year when the sun is directly above the equator. These events occur in spring and autumn and are significant astronomical events. As the term entered the English language, it retained this sense of the equalization of day and night during these two specific moments in the Earth's orbit around the sun. 'Equinox' thus reflects its Latin origins in the concept of equality and balance between day and night during these celestial occurrences.

Quiz: Find the meaning of equinox

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Further usage examples of equinox

1. The equinox is also known as the equinoctial point.
2. On the equinox, the Sun rises due east and sets due west.
3. Many ancient structures are aligned with the equinoxes.
4. Some cultures hold equinox festivals to honor nature and balance.
5. The equinox brings a sense of equilibrium to the natural world.
6. The equinox is often associated with the themes of balance, harmony, and unity.
7. Farmers pay attention to the equinox for planting and harvesting.
8. The equinox is a time of transition and change.
9. The equinox is a moment of cosmic symmetry.
10. The equinox is a popular topic in mythology and folklore.
11. Equinoxes have been observed and celebrated for millennia.
12. Scientists study the equinox to monitor Earth's axial tilt.
13. The equinox has cultural significance in many indigenous societies.
14. The equinox is one of the Earth's celestial phenomena.
15. The equinox is a time when the Sun crosses the celestial equator.
16. Some spiritual traditions meditate or reflect during the equinox for inner balance.



balance, solstice, imbalance, disproportion


ACT 1 (American College Testing), GRE 12 (Graduate Record Examination), Geography and Topography

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