Definition of "trilateral" [tri•lat•er•al]

• Having or involving three sides, countries, or parties. (adjective)

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.

• "We have for example promoted what we called a trilateral initiative between Afghanistan, Pakistan and Iran."
• "We have, for example, promoted what we call a trilateral initiative between Afghanistan, Pakistan and Iran."
• "In fact, right now he's in what they call a trilateral meeting with Palestinian and Israeli leaders."