Definition of "quintillionth" []

• The ordinal number matching the number quintillion in a series. (noun)
• One of a quintillion equal parts. (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.

• "Well, Horrors of War has one like it…except at about a quintillionth of the budget the beach at Normandy is like…four grains of sand and none of the acting ability"
• "Devised independently by Alan Guth of the Massachusetts Institute of Technology and by Russian physicist Andrei Linde, it holds that the universe began in the expanding fireball of the big bang and then inflated madly, doubling in size every tenth of a quadrillionth of a quintillionth (10-to the 34th power) of a second."
• "These, he calculated, had been created within the first hundred-quintillionth of a second after the big bang."