equinox

Meanings

1. 1nouncountable

   One of the two times each year when day and night are about the same length everywhere.

   Grammar: Countable: the spring equinox, two equinoxes a year. It usually appears with 'the' or with 'spring'/'autumn' before it.

   Patterns

   • the spring/autumn equinox
   • the equinox occurs in March
   • at the equinox

   The spring equinox usually falls on March 20 or 21.

   Many ancient cultures built monuments to mark the equinox.

   After the autumn equinox, the nights get longer quite quickly.

2. 2nouncountabletechnical

   Either of the two points on the sky's path where the sun crosses the equator.

   Grammar: Used in astronomy for the position as well as the date; often in the plural in this technical sense.

   Patterns

   • the vernal equinox
   • the autumnal equinox

   Astronomers refer to the March crossing as the vernal equinox.

   The satellite's position is measured relative to the equinox.

Word forms

Common combinations

the spring equinox

We plant our seeds just after the spring equinox.

the autumn equinox

The autumn equinox marks the start of shorter days.

the vernal equinox

The vernal equinox is the astronomical beginning of spring.

the autumnal equinox

The autumnal equinox falls in late September in the northern hemisphere.

celebrate the equinox

The village celebrates the equinox with a bonfire.

Synonyms and how they differ

equinoctial point

A technical term for the same position in the sky; 'equinox' is the everyday word for both the date and the point.

Opposites

Word family

equinoctial adjective

Relating to an equinox or to equal day and night.

equinoxes noun

The plural form, used for both annual events together.

Commonly confused: equinox or solstice? equinox or eclipse?

Practice

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