To strike or assault someone violently and severely, typically on the head. He warned me that he was going to brain me if I didn't stop insulting him. The lump on my head is from when a box fell off a shelf and brained me yesterday.
See also: brain
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
Fig. to strike a person hard on the skull as if to knock out the person's brains. (Often said as a vain threat.) I thought he was going to brain me, but he only hit me on the shoulder. If you don't do it, I'll brain you.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
Hit someone hard on the head. For example, The roof collapsed and a bunk of plaster brained him, or I'll brain you if you don't get to those dishes! This term is used both literally (first example) and hyperbolically (second example). [Slang; 1930s]
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
1. n. a good student; a very intelligent person. (see also brains.) I’m no brain, but I get good grades.
2. tv. to hit someone (in the head). I ought to brain you for that!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.