observatory

American  

[uhb-zur-vuh-tawr-ee, -tohr-ee] / əbˈzɜr vəˌtɔr i, -ˌtoʊr i /

noun

observatories plural

1. a place or building equipped and used for making observations of astronomical, meteorological, or other natural phenomena, especially a place equipped with a powerful telescope for observing the planets and stars.

2. an institution that controls or carries on the work of such a place.

3. a place or structure that provides an extensive view; lookout.

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observatory British  

/ -trɪ, əbˈzɜːvətərɪ /

noun

1. an institution or building specially designed and equipped for observing meteorological and astronomical phenomena

2. any building or structure providing an extensive view of its surroundings

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Etymology

Origin of observatory

1670–80; < Latin observā ( re ) to observe + -tory ²

Explanation

An observatory is a structure that holds a large telescope for observing the stars and planets or some celestial event. If you want to check out a lunar eclipse, then head to your nearest observatory. Observatories for examining the distant sky are typically located far from large cities, since light pollution makes it more difficult to see celestial bodies like stars and planets, or events like meteor showers. Another kind of observatory is quite simply a very tall, often skinny building meant for looking down over a city or its coastline. Observatory comes from the verb observe, or "watch," which in turn is rooted in the Latin observare, "watch over or guard."

Example Sentences

In the 1890s, long-simmering dreams of an inhabited Mars found a foothold in the U.S., fanned by wealthy astronomer Percival Lowell, who built an Arizona observatory.

From The Wall Street Journal • Apr. 23, 2026

As part of her course she spent several months as an intern at the observatory, where she researched Ernst Öpik's life beyond his scientific achievements.

From BBC • Apr. 20, 2026

Arctic sea ice reached its lowest level ever recorded, statistically tying last year's record, a leading US climate observatory for this geopolitically significant region said on Thursday.

From Barron's • Mar. 26, 2026

The James Webb Space Telescope is the most advanced space observatory ever built for studying the universe.

From Science Daily • Mar. 17, 2026

He saw the great dome of the main observatory, a smaller one a little way off, and between them a group of administration buildings and domestic quarters.

From "The Subtle Knife" by Philip Pullman