Definition of "os" []

• A mouth or an opening. (noun)
• A bone. (noun)
• See esker. (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.

• "The respectful salutation of carrying the hand to the mouth, ad os, is the root of the Latin word adoro, adorare."
• "But, it's true that Mole Negro, one of the most reknowned Moles Oaxaqueños is made with very dark toasted chiles plus a little chocolate."
• "Second on the list of so-bad-they're-good things are the Octopus's sidekicks; besides his personal femme fatale, Silken Floss (Scarlet Johansson), there's his army of chunky clones (played by Louis Lombardi), all of whom have names ending in os, such as Pathos, Logos, and Huevos Rancheros, and all of whom have their names printed on their shirts."