zenith

American  

[zee-nith, zen-ith] / ˈzi nɪθ, ˈzɛn ɪθ /

noun

1. the point on the celestial sphere vertically above a given position or observer.

   Antonyms:

   nadir

2. a highest point or state; culmination.

   Synonyms:

   summit, apex

   Antonyms:

   nadir

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zenith British  

/ ˈziːnɪθ, ˈzɛnɪθ /

noun

1. astronomy the point on the celestial sphere vertically above an observer

2. the highest point; peak; acme

   the zenith of someone's achievements

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zenith Scientific  

/ zē′nĭth /

1. The point on the celestial sphere that is directly above the observer (90 degrees above the celestial horizon).

2. Compare nadir

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Other Word Forms

• zenithal adjective

Etymology

Origin of zenith

1350–1400; Middle English cenith < Medieval Latin < Old Spanish zenit, scribal error for zemt < Arabic samt road, incorrectly read as senit by medieval scribes (compare Arabic samt ar-rās road above (over) one's head, the opposite of nadir )

Explanation

Zenith means the high point — it comes from astronomy, where it describes the highest point in an arc traveled by a star or a planet or another celestial body. The sun reaches its zenith when it is as high in the sky as it is going to go on that day. Zenith — and its opposite, nadir — have been appropriated by non-astronomers and are used to describe high and low points in non-astronomical contexts. For example, you can say that the high school quarterback hit his zenith in high school, and it was all downhill from there. Do yourself a favor and try to delay your zenith so you'll have something to look forward to in your future!

Example Sentences

The phrasing hit its zenith in the second half of 2025, with AlphaSense logging 73 documents with such sentence structure in the final quarter, or more than once a business day.

From Barron's • Apr. 14, 2026

Was Liu’s skate the zenith moment from these Milan Cortina Games?

From The Wall Street Journal • Feb. 23, 2026

Her musical zenith came thanks to hit songs “Jolene,” “Here You Come Again,” and “9 to 5,” the title track from the 1980 film where Parton also made her screen debut.

From Los Angeles Times • Jan. 22, 2026

When Congress and the president act in concert, the president’s power is at its zenith.

From Slate • Sep. 1, 2025

When Krete was out of sight astern, no land anywhere to be seen, but sky and ocean, Kronion put a dark cloud in the zenith over the ship, and gloom spread on the sea.

From "The Odyssey" by Homer