Definition of "macron" [ma•cron]

• A diacritical mark placed above a vowel to indicate a long sound or phonetic value in pronunciation, such as (ā) in the word make. (noun)
• The horizontal mark ( ¯ ) used to indicate a stressed or long syllable in a foot of verse. (noun)

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.

• "Now I know that the long mark is called a macron and the short mark is called a breve."
• "For years, though, the dude studying the macron was my pet example of scholarship's willful obscurity; I'm pretty sure I trotted out that story more than once when explaining why I didn't think I should go to grad school."
• "These are differentiated in the beginner Latin-Reader textbooks using a 'macron' which is a bar that goes over the long characters."