A person who stares openly and often rudely at something or someone, usually appearing foolish or vacant.
From 'gawk' plus the agent noun suffix '-er'; similar formation to 'looker' or 'walker'; entered English in the 1700s-1800s as informal vocabulary.
The word 'gawker' became especially common during the 19th-century rise of public spectacles and crowds—it's basically the birth of the term for rubber-necking, that universal human impulse to stare at accidents and unusual sights.
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