Bittern

1. a. A very bitter compound of quassia, cocculus Indicus, etc., used by fraudulent brewers in adulterating beer.
2. n. A wading bird of the genus Botaurus, allied to the herons, of various species.
3. a. The brine which remains in salt works after the salt is concreted, having a bitter taste from the chloride of magnesium which it contains.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.