The word "observed" means to see, watch or notice something. There are many synonyms for this word including "spotted", "noted", "witnessed", "perceived" and "noticed". Each of these words conveys a slightly different meaning. For example, "spotted" suggests a quick sighting while "noted" implies more intentional observation. "Witnessed" emphasizes the act of being a witness while "perceived" indicates a more subjective perception. "Noticed" is perhaps the most neutral and straightforward synonym. Regardless of which word is used, each conveys the idea of seeing or observing something with attention or interest.