To knock down; lay low: The boxer was flattened with one punch. (verb-transitive)
To become flat or flatter.(verb-intransitive)
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 "flatten" in a sentence
"Even in composing arrays, you need to first compose it the way you would in perl and then call the flatten method on that list in order to make it what you want."
"I mean, we have to kind of flatten out our icons, and for some reason we like our women tragic."
"But I'm also interested in how it can potentially 'flatten' the very flavors that make each culture unique."