Diacritic - Alphabetization or Collation

Alphabetization or Collation

Different languages use different rules to put diacritic characters in alphabetical order. French treats letters with diacritical marks the same as the underlying letter for purposes of ordering and dictionaries.

The Scandinavian languages, by contrast, treat the characters with diacritics ä, ö and å as new and separate letters of the alphabet, and sort them after z. Usually ä is sorted as equal to æ (ash) and ö is sorted as equal to ø (o-slash). Also, aa, when used as an alternative spelling to å, is sorted as such. Other letters modified by diacritics are treated as variants of the underlying letter, with the exception that ü is frequently sorted as y.

Languages that treat accented letters as variants of the underlying letter usually alphabetize words with such symbols immediately after similar unmarked words. For instance, in German where two words differ only by an umlaut, the word without it is sorted first in German dictionaries (e.g. schon and then schön, or fallen and then fällen). However, when names are concerned (e.g. in phone books or in author catalogues in libraries), umlauts are often treated as combinations of the vowel with a suffixed e; Austrian phone books now treat characters with umlauts as separate letters (immediately following the underlying vowel).

In Spanish, the grapheme ñ is considered a new letter different from n and collated between n and o, as it denotes a different sound from that of a plain n. But the accented vowels á, é, í, ó, ú are not separated from the unaccented vowels a, e, i, o, u, as the acute accent in Spanish only modifies stress within the word or denotes a distinction between homonyms, and does not modify the sound of a letter.

For a comprehensive list of the collating orders in various languages, see Collating sequence.