slip one's mind
Be overlooked or forgotten, as in I meant to pick up the wine but it slipped my mind. This idiom was first recorded about 1340.
Quotes On The Importance Of Your MindRead more in this article about some frequently asked questions and fun facts related to our definitions.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.