Diacritics are marks added above or below a letter or sometimes within or between letters. In the Roman alphabet, they are basically used to indicate a modification in how a letter sounds.

While some other European languages make use of a large number of diacritics, modern English does not have any. However, some borrowed words may be written in English with their original non-English diacritic. The most common are the grave (`) or acute (´) accents, the cedilla (¸), the umlaut/diaeresis (¨), the tilde (˜) and the circumflex (ˆ), but they rarely affect pronunciation (for exceptional cases, see Ambiguity below). Overall, borrowed words tend to lose their diacritics over time because of processes of simplification and assimilation, and because they are not easily typed on an English keyboard.

• Ambiguity
  
  Use diacritics when their absence could result in ambiguity. For example, exposé, resumé and rosé, when unaccented, look like different words (in this case, expose, resume and rose, respectively). In many cases, when there is no possible ambiguity, you do not need to use the original diacritic (for example, facade, deja-vu or doppelganger). In other cases, however, assimilated foreign words, including some borrowed from French (for example, attaché, communiqué, soufflé or papier-mâché) and, increasingly, from Spanish (jalapeño and piñata), often keep their original diacritics.
  
  
• Names
  
  With names in other languages, respect people’s uses of diacritics.
  
  

  Please contact Dr González Martí, assistant rector for Communication, for further information.

  
  

  The plenary talk was given by Professor Johan Lübeck, a specialist in medieval German manuscripts.

  
  
  
  
• Other words
  
  When an English text uses foreign words or phrases that are not names but that have a diacritic in the original language, you should either keep all such marks or else use none at all. Be consistent. If you decide to use them, remember that they should also be used on capital letters.
  
  

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