sukun

So when a waaw or yaa 'has a sukun over it, you know that the sound is a diphthong!

Arabic for Dummies Bouchentouf, Amine 2006

A sukun is similar to the main vowels in that it's a little symbol (a small circle) that you place above

Arabic for Dummies Bouchentouf, Amine 2006

However, unlike the vowels, you don't vocalize the sukun -- it's almost like a "silent" vowel.

Arabic for Dummies Bouchentouf, Amine 2006

There's an easy way to determine which is which: When either the yaa 'or the waaw is a diphthong, you see a sukun (soo-koon) above the consonant.

Arabic for Dummies Bouchentouf, Amine 2006

Because the sukun and the shadda also effect the pronunciation, are also usually left out, and are not vowels.

languagehat.com: AOUN. 2005

I also require full vowel/shadda/sukun pointing, gender and plurals indicated and, preferably, semitic root.

languagehat.com: ABU GHRAIB. 2005

The sutun kapas, and sukun biji or kalawi, are two species of the bread-fruit-tree (Artocarpus incisa).

The History of Sumatra Containing An Account Of The Government, Laws, Customs And Manners Of The Native Inhabitants William Marsden 1795