Sunan Abi Dawud, Hadith 4553

Narrated Al-Miswar b. Makhramah: 'Umar consulted the people about the compensation of abortion of woman. Al-Mughirah b. Shu'bah said: I was present with the Messenger of Allah when he gave judgement that a male or female slave should testify you. So he brought Muhammad b. Maslamah to him. Harun added: He then testified him. Imlas means a man striking the belly of his wife. Abu Dawud said: I have been informed that Abu 'Ubaid said: It (abortion) is called imlas because the woman causes it to slip before the time of delivery. Similarly, anything which slips from the hand or from some other thing is called malasa (slipped).

حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، وَهَارُونُ بْنُ عَبَّادٍ الأَزْدِيُّ، - الْمَعْنَى - قَالاَ حَدَّثَنَا وَكِيعٌ، عَنْ هِشَامٍ، عَنْ عُرْوَةَ، عَنِ الْمِسْوَرِ بْنِ مَخْرَمَةَ، أَنَّ عُمَرَ، اسْتَشَارَ النَّاسَ فِي إِمْلاَصِ الْمَرْأَةِ فَقَالَ الْمُغِيرَةُ بْنُ شُعْبَةَ شَهِدْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم قَضَى فِيهَا بِغُرَّةٍ عَبْدٍ أَوْ أَمَةٍ ‏.‏ فَقَالَ ائْتِنِي بِمَنْ يَشْهَدُ مَعَكَ ‏.‏ فَأَتَاهُ بِمُحَمَّدِ بْنِ مَسْلَمَةَ - زَادَ هَارُونُ - فَشَهِدَ لَهُ يَعْنِي ضَرَبَ الرَّجُلُ بَطْنَ امْرَأَتِهِ ‏.‏ قَالَ أَبُو دَاوُدَ بَلَغَنِي عَنْ أَبِي عُبَيْدٍ إِنَّمَا سُمِّيَ إِمْلاَصًا لأَنَّ الْمَرْأَةَ تَزْلِقُهُ قَبْلَ وَقْتِ الْوِلاَدَةِ وَكَذَلِكَ كُلُّ مَا زَلَقَ مِنَ الْيَدِ وَغَيْرِهِ فَقَدْ مَلِصَ ‏.‏

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also referenced under: Hadith 4570 (DarusSalam)