The last person to drop out in an auction; the second-highest bidder.(noun)
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Use "underbidder" in a sentence
"The underbidder was the Metropolitan Museum of Art. Asked recently to name a single work that he regretted not acquiring, the Met's outgoing director, Philippe de Montebello, responded, "The Rubens.""
"The National Gallery was the underbidder at that auction, but after the sale it was able to cut a deal to secure the work for the collection."
"We were the underbidder on the GOLD Pan Pac which sold for a whopping $345,000.00."