In some Semitic languages, such as Arabic, nunation (Arabic: تَنوِين tanwīn) is the addition of one of three vowel diacritics (Arabic: حَرَكَات ḥarakāt) to a noun or adjective to indicate that the word ends in an alveolar nasal without the addition of the letter nūn. The noun phrase is fully declinable and syntactically unmarked for definiteness.
In Classical and Modern Standard Arabic orthography, there are three
nunation diacritics, which indicate the suffixes -un (IPA: /-un/)
(nominative case), -in /-in/ (genitive), and -an /an/ (accusative).
The sign ـً is most commonly written in combination with ا
alif (ـًا), ةً (tāʾ marbūṭa تاء مربوطة) or
stand-alone ءً (hamza همزة). In the regional varieties of
Arabic, these diacritics are usually unwritten; however, the alif,
tāʾ marbūṭa or hamza is written.
Since Arabic has no indefinite article, nouns that are nunated are
often indefinite. However, many definite nouns can also be nunated:
for example, in the expression أَشْهَدُ أَنَّ
مُحَمَّدًا رَسُولُ الله ('ašhadu 'anna
Muḥammadan rasūlu l-lāh(i) /ʔaʃhadu ʔanna muħammadan
rasuːlu‿llah/ "I witness that
Arabic diacritics mimation iʿrāb