ma·cron (mākrŏn′, -krən, măkrŏn′)
1. A symbol ( ¯ ) placed over a vowel to show that it has a long sound.
2. The horizontal mark ( ¯ ) used to indicate a stressed or long syllable in a foot of verse.
[Greek makron, from neuter of makros, long; see māk- in the Appendix of Indo-European roots.]
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