Definition of "menstruum" [men•stru•um]

• A solvent, especially one used in extracting compounds from plant and animal tissues and preparing drugs. (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.

• "It is what chemists would call the 'menstruum' in which all our qualities are worked and made manifest, which holds them together."
• "Keeping this doughty resolution, he sat down to dinner with his counsel learned in the law; and speedily they dispatched the dish of chops which was set before them, and the better part of the bottle of old port, which served for its menstruum."
• "So the Wazir bade unbind him and he rose and taking virgin glass,554 brayed it and mixed it with unslaked lime and a menstruum of onion-juice."