observer

noun

ob·​serv·​er əb-ˈzər-vər 

: one that observes: such as

a

: a representative sent to observe but not participate officially in an activity (such as a meeting or war)

b

: an expert analyst and commentator in a particular field

political observers

Synonyms

• bystander
• onlooker
• spectator
• viewer
• watcher

Examples of observer in a Sentence

According to one observer, the event was poorly organized.

The star is not visible to an observer without a telescope.

According to one military observer, this change comes after years of planning.

Observers say the economy is improving.

The class has an observer today, so please be on your best behavior.

Recent Examples on the Web

The Role of the United States To claim that the U.S. is merely a passive observer is both inaccurate and misleading. —Andy J. Semotiuk, Forbes.com, 20 June 2025

But given that both the lander and tanker Starships will use up most of their propellant just getting into orbit, some independent observers estimate as many as 10 to 20 launches will be needed to gas up the lander for the flight to the moon. —William Harwood, CBS News, 19 June 2025

International observers say Iran is enriching uranium to a level that far exceeds what would be needed for civil energy purposes. —Shane Croucher john Feng, MSNBC Newsweek, 18 June 2025

In 2014, he was diagnosed with Graves’ disease, an autoimmune disorder, and his physical health became a subject of concern among observers. —Natalie Meade, Rolling Stone, 16 June 2025

Word History

Etymology

observe + -er entry 2

First Known Use

circa 1550, in the meaning defined above

Phrases Containing observer

• casual observer
• inter-observer

Rhymes for observer

• preserver
• fervor
• fervour
• server