Overview

The macron ( ¯ ) is a small horizontal bar written above a letter. Its name comes from the Greek makrón, meaning "long." In many writing systems the macron functions as a diacritic added to a character—most often to vowels—to indicate a phonetic property such as vowel length or stress.

Appearance and technical notes

Visually the macron is a short straight line centered over a single glyph. It may be represented as a combining character in Unicode or as precomposed letters in extended Latin blocks. Rendering depends on fonts and text layout systems; some environments place a longer overline when the intent is a typographic rule rather than a diacritic.

Functions in languages and transcription

Across languages and scholarly traditions the macron most commonly marks long vowels. It appears in classical language studies to show vowel length, in academic transliteration systems for Arabic and other languages to indicate long vocalic sounds, and in the orthographies of several modern languages to distinguish vowel quantity. Romanization schemes for East Asian languages sometimes use a macron to show a sustained vowel in pronunciation guides.

Examples and common uses

  • Scholarly Latin and Greek: used to denote long vowels in educational texts.
  • Language orthographies: employed in some Polynesian and Baltic languages and in other minority-language writing systems to mark vowel length.
  • Transliteration: appears in academic systems to render long vowels from non‑Latin scripts into Latin letters.

The macron is distinct from a breve (which often marks a short vowel), an acute or grave accent (which usually signals stress or tone), and an overline (a longer horizontal rule used for mathematical notation or editorial marks). In phonetic transcription the International Phonetic Alphabet typically uses a separate length sign, but the macron remains common in pedagogical and historical contexts.

Input and encoding

Writers can produce macronized letters via keyboard dead keys, input methods, or by using combining diacritics in Unicode. Many typesetting systems offer shorthand (for example, some TeX formats support \=a to create ā). Support for macrons is widespread in modern fonts and software, though precise placement may vary by typeface.

For further reading on etymology and usage see specialized references on diacritics and orthography; general overviews are available in linguistic handbooks and style guides.