ob·serv·er 
/əbˈzɚvɚ/ noun
plural ob·serv·ers /əbˈzɚvɚ/ noun [count] 1 : a person who sees and notices someone or something
▪ According to one observer, the event was poorly organized. ▪ The star is not visible to an observer without a telescope. ▪ Even a casual observer [=even someone who is not looking carefully] can tell that the building is in need of repair. 2 : a person who pays close attention to something and is considered to be an expert on that thing
▪ According to one military observer, this change comes after years of planning. ▪ Observers say the economy is improving. 3 : a person who is present at something (such as a meeting) in order to watch and listen to what happens
▪ The class has an observer today, so please be on your best behavior. 4 — used in the names of newspapers and magazines ▪ the Raleigh News and Observer ▪ the London Observer
▪ According to one observer, the event was poorly organized. ▪ The star is not visible to an observer without a telescope. ▪ Even a casual observer [=even someone who is not looking carefully] can tell that the building is in need of repair.
▪ 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.
