A man who is a nonprofessional: His is just the layman's view of medicine. See Usage Note at man.(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 "layman" in a sentence
"Probably took hand in more constitutional questions than anybody in history, and you'll find his decisions always had what I call layman's language in part of them, so they'd understand it."
"Now, Gentlemen, if our layman is a stockholder, he may figure something like this"
"In debate this is called "dropping the argument"; in layman's terms, it means that if you don't address it, you have conceded that your opponent is correct."