اثنا عشر
Masculine: ITH-nah AH-shar (the 'th' as in 'this', emphasis on first syllable of each word). Feminine: ITH-nah-tah ash-RAH (with a 'ta' sound at the end of the first word, emphasis on second syllable of 'ashrah'). The 'ع' in عشر is a pharyngeal sound from the throat with no English equivalent.
The number 12 in Arabic is written as "اثنا عشر" (ithna ashar) for masculine nouns and "اثنتا عشر" (ithnata ashar) for feminine nouns. As a compound number in the teens (11-19), it consists of two parts: the ones digit (اثنا/اثنتا meaning "two") followed by عشر/عشرة (meaning "ten"). This number follows unique grammatical rules as part of the special category of Arabic compound numbers.
The number 12 exhibits compound number grammar where both parts must agree in gender with the counted noun, but in opposite ways. The first part (اثنا/اثنتا) matches the gender of the noun (اثنا for masculine, اثنتا for feminine), while the second part (عشر/عشرة) takes the opposite gender (عشر for masculine nouns, عشرة for feminine nouns). The counted noun always appears in the singular form and takes the accusative case (منصوب) with tanween, marked by fatḥatayn (ً). In the construct state (إضافة), both parts of 12 can change: اثنا عشر becomes اثني عشر for masculine in non-nominative cases, and اثنتا عشرة becomes اثنتي عشرة for feminine in non-nominative cases. When used as an ordinal number (twelfth), it becomes الثاني عشر (masculine) or الثانية عشرة (feminine), and both parts take the definite article and agree with the noun's gender normally.
The number 12 holds significant religious importance in Islamic tradition, most notably as the number of months in the Islamic lunar calendar (الأشهر الاثنا عشر). The Quran specifically mentions in Surah At-Tawbah (9:36) that "Indeed, the number of months with Allah is twelve months," establishing this as a divinely ordained structure. Additionally, twelve has historical significance as the number of Imams in Shia Islam and appears in various Islamic contexts including the twelve springs that gushed forth for the twelve tribes of Israel as mentioned in the Quran.
In Arabic, the number 12 is one of only two teen numbers (along with 11) where the first component explicitly shows duality from the root "ث-ن-ي" (th-n-y) meaning "two" or "second." The word عشر (ashar) comes from the root "ع-ش-ر" (ayn-shin-ra) which gives us عشرة (ten) and عشيرة (tribe/clan of about ten families). Interestingly, when Arabs tell time using the twelve-hour clock, they must use the ordinal form, so "twelve o'clock" becomes "the twelfth hour" (الساعة الثانية عشرة), making it one of the most commonly spoken compound numbers in daily conversation.