A floating structure, such as a flatbottom boat, that is used to support a bridge.(noun)
A floating structure serving as a dock.(noun)
A float on a seaplane.(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 "pontoon" in a sentence
"The party boat is what we called the pontoon boat."
"It could very well have been "pontoon" on a different day."
"Other games are "crown and anchor", which is a dice game, and "pontoon", which is a card game similar to "twenty-one" or "seven and a half.""