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n. Slang A gawking onlooker.

n. Someone who watches, a spectator, in the sense that they crane their neck as though it were made of rubber. Especially those who watch accidents.

n. a person who stares inquisitively

"I felt like a rubbernecker, but was compelled to know more about this lady."

looker    watcher    spectator    viewer    witness   

rubberneck    rubbernecking