-oon

-oon

a suffix occurring in words borrowed from French and other Romance languages (bassoon; balloon; dragoon; pontoon), occasionally used in the formation of new nouns in English (spittoon).
[as an English formative representing chiefly French -on in words stressed on the final syllable]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.