A (usually) antique item, such as a clock, radio, sewing machine, spinning wheel, tool,car parts, etc, that may or may not work, kept strictly as a display item. More often than not the item does not work but the owner has no intention of repairing it, it just sits there.

If it is sometimes used and is not strictly a decoration it is NOT a shelf queen.
"Did Joe ever get that Sparton Bluebird working?"

"No, it's just a shelf queen for his mantel. Thousands of dollars for a non-working radio, just for display!"
by Old Radio Collector November 21, 2006
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Someone who buys video games with no intention of playing them and only uses them as decorations and for hopes that they will one day be worth lots of money.
These fucking shelf queens are causing retro games to go up in value.
by ghostthecuck May 13, 2016
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