Definition of "heavy metal" [heavy metal]

• A metal with a specific gravity greater than about 5.0, especially one that is poisonous, such as lead or mercury. (noun)
• Music Very loud, brash rock music, often with shouted, violent lyrics. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Recent studies into how differently individuals process one particular autogen, the heavy metal mercury, bear this out all too perfectly."
• "Bloodbath would keep singing this song for the rest of his life and would later teach it to his children and grandchildren, who would eventually move around quite a bit, to England, to Germany—and some of them even to a small town in Minnesota, where they would form the heavy metal band Meat Ball, which would become famous after being featured in the mockumentary There Will Be Life Here."
• "There has never been a clinical trial testing chelation for autism; one government-funded trial was halted after scientists at Cornell University and the University of California, Santa Cruz, found that rats without heavy metal poisoning who were chelated showed signs of cognitive impairment."