observatory

noun

ob·​ser·​va·​to·​ry əb-ˈzər-və-ˌtȯr-ē 

plural observatories

1

: a building or place given over to or equipped for observation of natural phenomena (as in astronomy)

also : an institution whose primary purpose is making such observations

2

: a situation or structure commanding a wide view

Synonyms of observatory

• tower
• overlook
• lookout

Examples of observatory in a Sentence

the observatory is located on a mountaintop

Recent Examples on the Web

The atmospheric phenomena potentially detectable by HWO depend on those phases and the angle between the planet, its star, and the observatory, and therefore are best seen at different times in the planet’s orbit. — Phil Plait, Scientific American, 2 Oct. 2026

The reboost attempt would be moot if the atmosphere dragged the Swift observatory toward reentry before Katalyst could launch Link in pursuit. — Stephen Clark, ArsTechnica, 1 Oct. 2026

The 3,200-pound (1,452-kilogram) observatory is currently located about 200 miles (325 kilometers) above Earth. — Ashley Strickland, CNN Money, 30 Sep. 2026

Swift has resumed scanning for gamma-ray bursts and exploding stars, but NASA is scrambling to replace the observatory’s role as a rapid-response lookout for other telescopes. — Marcia Dunn, Los Angeles Times, 27 Sep. 2026

Word History

Etymology

borrowed from New Latin observātōrium "place for observing celestial phenomena," from Latin observāre "to give attention, watch carefully, observe" + -tōrium, suffix of place, noun derivative from neuter of -tōrius, deverbal adjective suffix originally forming derivatives from agent nouns ending in -tōr-, -tor

First Known Use

1673, in the meaning defined at sense 1

Rhymes for observatory

• accusatory
• admonitory
• ambulatory
• amendatory
• celebratory
• circulatory
• combinatory
• commendatory
• compensatory
• condemnatory
• confirmatory
• confiscatory

Kids Definition

observatory

noun

ob·​ser·​va·​to·​ry əb-ˈzər-və-ˌtōr-ē 

-ˌtȯr-

plural observatories

1

: a place or institution equipped with instruments for observation of natural objects and events (as in astronomy)

2

: a place providing a wide view