observer

noun

ob·​serv·​er əb-ˈzər-vər How to pronounce observer (audio)
Synonyms of observernext
: 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

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
On Friday, observers spotted what appeared to be a pip — or breach in the eggshell. Lila Seidman, Los Angeles Times, 4 Apr. 2026 Interestingly, the planet's greatest altitude at sunset will also be occurring at this time, when the ecliptic (the apparent path of the sun, moon and planets throughout the year) becomes nearly vertical with respect to the western horizon for observers in northern latitudes. Joe Rao, Space.com, 3 Apr. 2026 Many observers, like The New York Times’ Silicon Valley correspondent Mike Isaac, said TBPN amounts to a form of marketing for OpenAI. Brian Stelter, CNN Money, 3 Apr. 2026 Relative motion of source and observer. Big Think, 3 Apr. 2026 See All Example Sentences for observer

Word History

Etymology

observe + -er entry 2

First Known Use

circa 1550, in the meaning defined above

Time Traveler
The first known use of observer was circa 1550

Cite this Entry

“Observer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/observer. Accessed 5 Apr. 2026.

More from Merriam-Webster on observer

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster