A person who observes something; a witness. Obsolete. rare.

A person who looks at something with care or attention; a person who closely observes or scrutinizes something; a person who sets out to view…

An observer or recorder. Obsolete.

A person who watches or takes notice; = observer, n. 2a. Obsolete.

A person who makes or utters observations on someone or something; a critical observer. Now usually: a person who makes a particular remark.

A person who notices or perceives something; an observer.

A person who observes in an official capacity without participating; spec. (a) one who attends a conference, inquiry, etc., to note the…

In extended use. A person who (or occasionally a thing which) watches someone or something. Originally Military. Someone or something positioned so…