corundum


co·run·dum

noun \kə-ˈrən-dəm\

Definition of CORUNDUM

: a very hard mineral Al2O3 that consists of alumina occurring in massive form and as variously colored crystals which include the ruby and sapphire

Test Your Vocabulary

Take Our 10-Question Quiz

Name That Thing

Take our visual vocab quiz

Test Your Knowledge »

True or False?

A quick quiz about stuff worth knowing

Take It Now »

Join Us on FB & Twitter

Get the Word of the Day and More

Facebook | Twitter

Get Our Free Apps

Voice Search, Favorites,
Word of the Day, and More

iPhone | iPad | Android | More