A strong, low-density, highly corrosion-resistant, lustrous white metallic element that occurs widely in igneous rocks and is used to alloy aircraft metals for low weight, strength, and high-temperature stability. Atomic number 22; atomic weight 47.87 melting point 1,660°C; boiling point 3,287°C; specific gravity 4.54; valence 2, 3, 4. See Table at element.
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.