Informal Something, such as a structure or sandwich, that has three decks, floors, or layers. (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.
Use "triple-decker" in a sentence
"I pull up to Barney's "triple-decker," a somewhat run-down example of the three-floored apartment buildings that make up much of Boston's older housing stock."
"Their beat was a rhythmic triple-decker — and a new approach to R & B."
"The triple-decker pastrami, corned beef and salami sandwich with Russian dressing $23 borders the structurally unsound."