Sahih Muslim 12806
In-book no 5529وَحَدَّثَنِي أَبُو الطَّاهِرِ، أَخْبَرَنَا ابْنُ وَهْبٍ، قَالَ سَمِعْتُ اللَّيْثَ بْنَ سَعْدٍ، يَقُولُ الْحَمْوُ أَخُ الزَّوْجِ وَمَا أَشْبَهَهُ مِنْ أَقَارِبِ الزَّوْجِ ابْنُ الْعَمِّ وَنَحْوُهُ .
Ibn Wahb reported: I heard Laith b. Said as saying: Al-Hamv means the brother of husband or like it from amongst the relatives of the husband, for example, cousin, etc.