What is the duration denoted by 'ten' when calculating the waiting period (Iddah)?

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The obligatory period considered for the Iddah is ten nights including their days, thus ten full days with the nights are required. This view is held by Malik, Al-Shafi'i, Abu Ubaid, Ibn al-Mundhir, and the companions of Al-Ra'y (Hanafi school). The evidence for including days when 'nights' are mentioned lies in the Arabic usage where the feminine form of the number, like 'layali' (nights), is often used inclusively to mean the nights along with their corresponding days. This is supported by the usage in the Quran where Zakariyya was told he would not speak for 'three nights' (Quran 19:10), which is clarified elsewhere to mean 'three days' (Quran 3:41), implying inclusion.