Scottish Gaelic orthography has evolved over many centuries. Scottish Gaelic spelling is mainly based on etymological considerations.
Due to the etymological nature of the writing system, the same written form may result in a multitude of pronunciations depending on the spoken variant. For example, the word coimhead "watching" may result in [kʰõ.ət̪], [kʰɔ̃jət̪], [kʰʷi.ət̪], or [kʰɛ̃.ət̪].
The alphabet is known as the aibidil in Scottish Gaelic, and formerly the Beith Luis Nuin from the first three letters of the Ogham alphabet: b, l, n. The alphabet now used for writing the Scottish Gaelic language consists of the following letters of the Latin alphabet, whether written in Roman type or Gaelic type:
Modern loanwords also make use of j k q v w x y z.
From a language internal perspective, the following digraphs are considered single letters:
Older manuscripts made use of the acute accent over vowels, but these are no longer used in standard orthography. Since the 1980s the acute accent has not been used in Scottish high school examination papers, and many publishers have adopted the Scottish Examination Board's (the Scottish Qualifications Authority's after 1997) orthographic conventions for their books. The acute accent is still used in most Scottish universities (and several Scottish academics remain vociferously opposed to the SEB's/SQA's conventions) and by a minority of Scottish publishers, as well as in Canada.