bittering agent

noun

: an ingredient added to a substance to give it a bitter flavor

The Sumerians flavored their beer with honey, while Europeans flavored and preserved their beer with a bittering agent such as hops.

—Bill Yenne, The American Brewery, 2003

Some pesticide makers thought putting a bittering agent into the poisons would make rats less likely to eat the products …

—Robert McClure, MSNBC.com, 22 Dec. 2010

The vast majority of automotive antifreeze contains ethylene glycol, though some contains a bittering agent to eliminate the sweet taste.

—Steven Cole Smith, Orlando Sentinel, 15 Apr. 2011

Word History

First Known Use

1895, in the meaning defined above

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