on the/(one's) brain(redirected from on his brain)
on the/(one's) brain
Occupying one's sole or most prominent attention or interest; forming an obsession or preoccupation for one. Tom's just got football on the brain—he's not really interested in anything else. I've had Alice on the brain all afternoon, and then she called me just now. What a coincidence! The strange history of this town has been on my brain ever since high school. I'd love to write a book or play about it.
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.
on the brain
Obsessively in mind: The coach has winning on the brain.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.