noun a wading bird of the genus botaurus, allied to the herons, of various species.
2. bittern ·adj a very bitter compound of quassia, cocculus indicus, ·etc., used by fraudulent brewers in adulterating beer.
3. bittern ·adj the brine which remains in salt works after the salt is concreted, having a bitter taste from the chloride of magnesium which it contains.