Abu Ubayd (may Allah have mercy on him) said: Some of them say "al-hiqaq", which comes from muhaqqah, meaning disputing: that the mother disputes with the paternal relatives (asabah) over the girls. So "nass al-hiqaq" is simply reaching maturity, because it is the end of childhood. When women reach that, the paternal relatives have more right to the woman than her mother, if they are mahram relatives, and likewise to marry her off if they wish. He said: This makes clear to you that the paternal relatives and guardians other than fathers may not marry off an orphan girl until she reaches maturity; if they had that right, they would not wait for "nass al-hiqaq" with her. He said: And whoever narrated it as "nass al-haqa'iq" meant it as the plural of haqiqah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 13696