gazillion definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
Slang a very large, indefinite number
Origin: arbitrary coinage ; from zillion
gazillion definition by American Heritage Dictionary
Informal An indefinitely large number: “The crowd cheered wildly . . . as gazillions of balloons poured down from the rafters” (Tom Shales).
Origin: On the model of million, billion, etc.