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.
Use "tetrahedral" in a sentence
"The lugsails are arranged in a tetrahedral, that is, each of the four lugsails is oriented exactly 109.47 degrees from the other three."
""That's a different kind," the Forecaster answered, "it's called a tetrahedral kite, and was invented by Dr. Alexander Graham Bell."
"The tetrahedral vessel would bounce and land on one of its faces, and one or the other of them would be right-side up and in a position to help the others."