An overwhelming outpouring: an onslaught of third-class mail. (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 "onslaught" in a sentence
"An angry Mr. Kasich tells me that this onslaught is the way it's been from the Strickland campaign for 14 straight months."
"It's clear to me that the media onslaught is the default."
"I think if we back him up he will be able to overcome this onslaught from the greedy power brokers and the congressmen that have their hands in the till."