home runn. Abbr. HR Baseball A hit that allows the batter to make a complete circuit of the diamond and score a run.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.home run n (Baseball) baseball a hit that enables the batter to run round all four bases, usually by hitting the ball out of the playing area Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014home? run? n. a hit in baseball allowing the batter to circle the bases and score a run. [1855?60, Amer.] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.home runA hit that allows the batter to get around all the bases in one turn.Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited