grow teeth
v. phr.— «A mysterious Taiwanese-born floor trader, Hwalin Lee, singlehandedly cost another CBOE clearing firm more than $50 million in a huge short position in S&P 100 puts that exploded into the money even before Oct. 19. In traders’ jargon, the puts “grew teeth.”» —“The Crash—One Year Later: In the Pits —How One Options Dealer Blew $9 Million” by Jonathan R. Laing Barron’s Oct. 17, 1988. (source: Double-Tongued Dictionary)
Further reading
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