A person who gazes or looks intently at something; one who habitually observes or watches.
From 'gaze' plus the agent suffix '-er' (indicating a person who performs an action), similar to 'runner' (one who runs), 'teacher' (one who teaches), and 'reader' (one who reads).
The '-er' suffix is English's oldest and most productive way to name people by their actions—you can add it to almost any verb and get a job title or descriptor, which is why we have everything from 'bakers' to 'dreamers.'
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