What is the minimum required area for wiping the head during Wudu if partial wiping is permitted?

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If wiping only a part of the head is deemed sufficient, wiping any location on the head suffices because the entire structure is considered the head, excluding the ears, which are subsidiary. The apparent position from Abu 'Abdillah (Ahmad) is that wiping the ears is not obligatory even if complete wiping is required, as the term 'head' when unrestricted only covers the area where hair grows. Al-Qadi states that wiping the forelock (*nasiyah*) is sufficient, based on the Prophet's action as a clarification of the command. Abu Al-Khattab and some Shafi'is narrated from Ahmad that wiping the majority of the head is required because the majority is what the complete name of the thing is applied to.