1. A grounded metal rod placed high on a structure to prevent damage by conducting lightning to the ground.
2. One that attracts and absorbs powerful, typically negative feelings and reactions, thereby diverting interest from other issues: "[His] business dealings have become a lightning rod for criticism" (Walter Shapiro).

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.