Christ·mas·time (kr?s?m?s-t?m?)n. The season of Christmas.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.Christ?mas?time (?kr?s m?s?ta?m) n. the Christmas season. [1830?40] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.