1.One who observes, or pays attention to, anything; especially, one engaged in, or trained to habits of, close and exact observation; as, an astronomical observer. "The observed of all observers." "Careful observers may foretell the hour, By sure prognostic, when to dread a shower."
2.One who keeps any law, custom, regulation, rite, etc.; one who conforms to anything in practice. "Diligent observers of old customs." "These... hearkened unto observers of times."
3.One who fulfills or performs; as, an observer of his promises.
4.A sycophantic follower. (Obs.)
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