Simple Definition of observer
: a person who sees and notices someone or something
: a person who pays close attention to something and is considered to be an expert on that thing
: a person who is present at something (such as a meeting) in order to watch and listen to what happens
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.
First Known Use of observer
Seen and Heard
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