Wiktionary
in layman's terms
prep.phr. (context idiomatic English) Phrased simply, without jargon.
Usage examples of "in layman's terms".
In civilian life, and in layman's terms, you would say she'd had a profound nervous breakdown.
She needed an expert consultant, somebody who either knew this area already or who could study and relate it to her in layman's terms.
Well, Lord Darcy, to put it in layman's terms, a powerful spell is placed upon the affected person -- a geas, it's called -- which forces him to limit his activities to those which are not dangerous to his fellow man.
But I can't get away from the subject of the interstellar drive without mentioning the one time he made an attempt to put it in layman's terms.