Tanwīn: ـٌ، ـٍ، ـً

Tanwīn “nunation” adds an n sound to the end of many indefinite nouns and adjectives in fully inflected Modern Standard Arabic. It has three written forms—ـٌ -un، ـٍ -in، ـً -an—which combine indefiniteness with nominative, genitive, or accusative case. The n is pronounced but is not written with the letter ن.

English has no comparable ending. Its articles usually mark “a student” versus “the student,” while Arabic coordinates the presence or absence of tanwīn with the noun phrase's definiteness and grammatical role. Ordinary unvocalized MSA usually omits the tanwīn marks, but accusative -an often leaves a visible support alif in the base spelling.

The three tanwīn marks

Tanwīn is visually a doubled short-vowel mark on the last pronounceable part of a word.

The first two ordinary spellings are identical: كتاب. The third has كتابا because fatḥ tanwīn normally requires an orthographic support alif. Fully vocalized text exposes all three endings; syntax tells an ordinary reader which one belongs in the sentence.

How case selects -un, -in, or -an

At this stage, think of case as the job a noun phrase performs. A typical subject is nominative, a noun after a preposition is genitive, and a direct object is accusative. Later case pages refine those categories, but this three-way contrast is enough to understand the spelling.

In the first sentence, طَالِبٌ is the subject. In the second, طَالِبٍ follows مَعَ and is genitive in this construction. In the third, كِتَابًا is the direct object. Its adjective also has accusative fatḥ tanwīn, though at the sentence-final pause جَدِيدًا is pronounced jadīdā, without the final n.

The examples deliberately pronounce internal case endings. Formal speakers vary: fully inflected reading is appropriate in careful news, ceremonial, or grammatical contexts, while much educated formal speech suppresses many endings. Tanwīn remains part of MSA grammar even when pause or speaking style makes it inaudible.

Tanwīn and indefiniteness

A regular indefinite noun or adjective can take tanwīn. Adding the definite article الـ blocks tanwīn because a phrase is not simultaneously article-definite and morphologically indefinite.

Notice that the article stays written الـ, while its l assimilates in pronunciation to the sun letter ط: aṭ-ṭālib. The definite noun has single ḍamma, not ḍammatān tanwīn.

Possessive constructions also suppress tanwīn on the possessed head noun:

Here طالب is made definite by its relationship to الجامعة, so it has -u, not -un. A possessive suffix has the same effect: fully marked كِتَابُهُ kitābuhu “his book,” never كِتَابٌهُ.

The support alif with fatḥ tanwīn

The -an mark normally appears with an extra final alif in the ordinary letter skeleton. The alif supports the spelling; in connected pronunciation the ending is -an, not -ān.

The exceptions are orthographic, so there is no useful English analogy to reason from; the letter classes must be learned. The Tāʾ Marbūṭa page explains why ة has its own behavior.

Tanwīn occurs at a word's end, not medially. If material is attached after the noun—such as a possessive suffix—the tanwīn disappears rather than moving into the middle. Likewise, the support alif belongs to the word form that actually has accusative -an; it is not a general feminine or plural ending.

Connected reading and pausal reading

When speech continues, the three endings are pronounced -un, -in, -an. At a natural pause, final -un and -in lose their case vowel and n, while -an normally becomes long -ā. A word ending in ةً instead pauses in -a(h).

This is why romanization on this page sometimes shows the full n and sometimes a pausal form: it follows what the fully vocalized spoken form is meant to represent, not merely the mark's dictionary name.

Ordinary and specialist notation

In ordinary (formal) MSA, حضر طالب جديد is normal and the reader infers the endings. Fully vocalized (formal/educational) text writes حَضَرَ طَالِبٌ جَدِيدٌ when every case ending is being demonstrated. (Quranic) orthography uses additional recitation signs and reading conventions; those should not be imported into a contemporary MSA exercise.

The unvocalized and vocalized versions still share one skeleton. For اشتريت كتابا, stripping the vowel and tanwīn marks from اِشْتَرَيْتُ كِتَابًا yields the displayed spelling, including the support alif.

Common Mistakes

1. Writing the pronounced n as ن

2. Omitting the fatḥ-tanwīn support alif

3. Adding a support alif after tāʾ marbūṭa

4. Combining the definite article and tanwīn

5. Pronouncing sentence-final -un at a natural pause

Key Takeaways

• The three tanwīn endings are nominative -un, genitive -in, and accusative -an; their n is never written with ن.
• A regular definite noun with الـ, a possessor, or a possessive suffix does not take indefinite tanwīn.
• Fatḥ tanwīn normally adds support ا, but not after ة، ى, or hamza already preceded by alif as in سماءً.
• Connected full endings and natural pausal readings differ: final -un/-in disappear, while ordinary -an pauses as -ā.