ت س عt-s-ʿ
— تِسْعtisʿ / تِسْعَةtisʿah: the number nine. The rule of numerals applies here too, that it takes the gender opposite to the counted noun. ﴿وَكَانَ فِي الْمَدِيْنَةِ تِسْعَةُ رَهْطٍ﴾ (An-Naml 27:48); ﴿تِسْعَ آيَاتٍ بَيِّنَاتٍ﴾ (Al-Isrāʾ 17:101)
تِسْعُوْنtisʿūn: ninety. ﴿اِنَّ هٰذَآ اَخِيْ لَهُۥ تِسْعٌ وَّتِسْعُوْنَ نَعْجَةً﴾ (Ṣād 38:23). This root occurs seven times in the Quran.