A person or creature that looks at or watches something, especially someone who examines or observes carefully.
From 'eye' (Old English 'ēge') + agent suffix '-er' (from Proto-Germanic 'az'). A straightforward formation meaning 'one who eyes.'
An eyer could be you window-shopping, a cat watching a bird, or a film critic analyzing every frame—it's a wonderfully simple word for all kinds of looking.
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