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 of observer

• spectator
• viewer

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

Built by aerospace contractor Lockheed Martin, X-59 is designed to not only break the sound barrier by surpassing Mach-1 speeds, but to do it without generating sonic booms that sound like cracks of thunder to observers on the ground. — Eric Lagatta, USA Today, 9 Sep. 2026

The perception of relationships between men and women will always be viewed differently by some observers. — Bobby Burack Outkick, FOXNews.com, 9 Sep. 2026

Early fall provides a good opportunity for northern hemisphere observers to look for zodiacal light before dawn, when the angle of the ecliptic helps the glow stand more prominently above the eastern horizon. — Jules-Pierre Malartre, Space.com, 9 Sep. 2026

Leclerc was fifth and 87 points down Ahead of Monza, some observers were already questioning whether Ferrari should start prioritizing its lead driver to mount a championship challenge. — Madeline Coleman, New York Times, 8 Sep. 2026

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