¯

A horizontal line to be placed above other characters. Also known as an upperscore.

¯

1. (linguistics) Used to indicate mid tone.
2. See ‾ for the overline, which is used in mathematics.

In English, this is called macron.

• ‾ (a line above, used to mark repeating digits)

¯

1. A diacritical mark of the Latin script, called マクロン (“macron”) in Japanese, and found on Ā/ā, Ē/ē, Ī/ī, Ō/ō and Ū/ū.

In a number of romanization systems of Japanese, particularly Hepburn, the macron indicates that a vowel is a long vowel.

Other romanization systems, particularly Kunrei-shiki, use the circumflex (^) for that purpose.

¯

1. A diacritical mark of the Latin script, called signum productionis (“macron”) in Latin, and found on Ā/ā, Ē/ē, Ī/ī, Ō/ō and Ū/ū. (used in grammars and dictionaries)

• ˘ (signum correptionis)

¯

1. A diacritical mark of the Latin script, called garumzīme (“macron”) in Latvian, and found on Ā/ā, Ē/ē, Ī/ī and Ū/ū.

• Used to mark long vowels: ā = [aː], ē = [ɛː] or [æː], ī = [iː], ū = [uː].
• For a short while (1908-1919), it was also used with the letter o (ō) to mark long [oː] in words of foreign origin, but this usage has since then been abandoned.
• Letters with macrons are considered as separate letters with different names, and listed in the alphabet after the same letters without macron (i.e., ā after a, ē after e, ī after i, and ū after u). In actual practice, however, letters with and without macrons are treated as the same letter in alphabetized lists (e.g., in dictionaries), unlike letters with cedillas (ģ, ķ, ļ, ņ) or háčeks (č, š, ž), which are kept separate in alphabetized lists.

¯

1. A diacritical mark of the Latin script, called 長音符號 (“macron”) in Mandarin, and found on Ā/ā, Ē/ē, Ī/ī, Ō/ō, Ū/ū and Ǖ/ǖ.