That is heard or that can be heard.
Football A new or substitute offensive play called by the quarterback or a defensive formation called by a linebacker at the line of scrimmage as an adjustment to the opposing side's formation. Also called automatic.
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.