n. The practice of winning an online auction by entering a last-second bid, often by using special software.
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Mr. Bauer also said that he had been the victim of "sniping," in which a nominal high bidder is picked off by an opportunistic rival as an auction's time limit is about to expire. It happened to him when he had been the high bidder on an 1860 election pamphlet throughout most of the proceedings. With a few minutes left for bidding, he had to leave his desk; when he returned, someone had outbid him by just $2.50, securing the pamphlet.
—Terry McManus, “Lincoln Artifacts Are Popular on Line,” The New York Times, October 22, 1998
"Sniping" — waiting until the 11th hour to enter a bid — has been elevated to an art form in online auctions, where bidders use e-mail and a mouse to haggle over all manner of goods from all over the world.
—Leslie Walker, “Going, Going . . .; Investors Bid Up Shares of Online Auction Firm,” The Washington Post, September 25, 1998
1998 (earliest)
Others go for manipulative maneuvers such as sniping — filing a bid at the last possible moment.

"I'll go to my bid page, type in the bid, and wait," Roth explains. "The countdown will say 58 seconds, and I'll sit there and go 57, 56 . . . and when it hits 10 seconds, I'll hit Enter."

Relying on sniping can backfire, Roth admits, when another sniper's bid is higher, or when heavy volume on the system slows processing.
—Denise Flaim, “Going, going, strong,” Newsday (New York, NY), June 04, 1998
A special Word Spy thank you goes out to Gareth Branwyn, proprietor of Wired magazine's excellent "Jargon Watch" column, for letting me know about this word.
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