Equinox

Noun

Definition: Either of the two times of the year (spring and autumn) when the sun crosses the equator and day and night are approximately equal in length.

Synonyms: March equinox, September equinox, Vernal equinox, Autumnal equinox

Antonyms: Solstice

Examples:

The equinox is a time of balance between day and night.
The vernal equinox marks the beginning of spring.

Mnemonics:

"Equal" in "equinox" represents the equal length of day and night.

Etymology:

Origin:

Late Middle English (denoting the time when daytime and nighttime are of equal duration): from Old French equinoxe or Latin aequinoctium, from aequi- ‘equal’ + nox, noct- ‘night’.

Historical Usage:

The term "equinox" has been used since the late Middle English period and comes from Old French and Latin origins.

Related Idioms:

Idiom:

"Vernal equinox"

Explanation:

This phrase refers specifically to the equinox that occurs in spring and marks the transition from winter to spring.

Misconceptions:

Misconception:

Equinoxes always have exactly equal lengths of day and night.

Explanation:

While the term "equinox" implies equal length, in reality, the lengths of day and night may vary slightly depending on one's location and atmospheric conditions.