- a person or thing that observes
- a person who attends a conference solely to note the proceedings
- a person trained to identify aircraft, esp, formerly, a member of an aircrew
WordReference Random House Unabridged Dictionary of American English © 2026
ob•serv•er
(əb zûr′vər),USA pronunciation n.
ob•serv′er•ship′, n.
- someone or something that observes.
- a delegate to an assembly or gathering, who is sent to observe and report but not to take part officially in its activities.
- Military[U.S. Air Force.]
- a member of an aircrew, other than the pilot, holding an aeronautical rating.
- a person who maintains observation in an aircraft during flight.
- MilitaryAlso called air observer, aircraft observer. [U.S. Army.]a person who serves in an aircraft as a reconnoiterer and directs artillery fire.
- observe + -er1 1545–55
Collins Concise English Dictionary © HarperCollins Publishers::
observer /əbˈzɜːvə/ n
ob•serve /əbˈzɜrv/USA pronunciation
v., -served, -serv•ing.
WordReference Random House Unabridged Dictionary of American English © 2026- to see, watch, or notice: [~ + object]I observed a person dashing across the field.[no object]I'm just observing; I'm not participating.
- to look at with attention: [~ + object]The scientists observed the eclipse.[no object]to observe and learn.
- to state by way of comment;
remark:[used with quotations]"You're simply not ready,'' he quietly observed. - to keep or maintain in one's action, conduct, etc.:[~ + object]to observe silence.
- to obey, comply with, or conform to:[~ + object]to observe the law.
- [~ + object] to celebrate, as a holiday, in a customary way.
ob•serve
(əb zûrv′),USA pronunciation v., -served, -serv•ing.
v.t.
v.i.
ob•serv•ed•ly
(əb zûr′vid lē),USA pronunciation adv.
ob•serv′ing•ly, adv.
v.t.
- to see, watch, perceive, or notice:He observed the passersby in the street.
- to regard with attention, esp. so as to see or learn something:I want you to observe her reaction to the judge's question.
- to watch, view, or note for a scientific, official, or other special purpose:to observe an eclipse.
- to state by way of comment; remark:He observed frequently that clerks were not as courteous as they used to be.
- to keep or maintain in one's action, conduct, etc.:You must observe quiet.
- to obey, comply with, or conform to:to observe laws.
- to show regard for by some appropriate procedure, ceremony, etc.:to observe Palm Sunday.
- to perform duly or solemnize (ceremonies, rites, etc.).
- to note or inspect closely for an omen or sign of future events.
v.i.
- to notice.
- to act as an observer.
- to remark or comment (usually fol. by on or upon).
- Latin observāre to watch, regard, attend to, equivalent. to ob- ob- + servāre to keep, save, pay heed to
- Middle French observer
- Middle English observen 1350–1400
- 2. note. Observe, witness imply paying strict attention to what one sees or perceives. Both are "continuative'' in action. To observe is to mark or be attentive to something seen, heard, etc.; to consider carefully; to watch steadily:to observe the behavior of birds, a person's pronunciation.To witness, formerly to be present when something was happening, has added the idea of having observed with sufficient care to be able to give an account as evidence:to witness an accident. 4. mention, say. 6. follow, fulfill. 7. celebrate, keep.
- 1. –3, 6–8. ignore.
'observer' also found in these entries (note: many are not synonyms or translations):
aberration
- altitude
- apparent
- auspex
- Brocken
- chroma
- colour
- constancy
- culminate
- dextrorotation
- distance
- Doppler effect
- eyepiece
- hand
- horizon
- Hubble's law
- hue
- iridescent
- lightness
- luminous
- meridian
- nadir
- O'Brien
- observation
- obverse
- o'clock
- parallax
- rangefinder
- rest mass
- ROC
- saturation
- spectator
- stadia
- stardust
- telemeter
- time
- zenith
- absolute magnitude
- acute
- advance
- aircraft observer
- air observer
- angular diameter
- anticorona
- apparent magnitude
- appearance
- astronomer
- blueshift
- brightness
- Brocken specter