ENOfficial
Ibn 'Abbas said that Juwayriyya's name had been Barra and the Prophet, may Allah bless him and grant him peace, had renamed her Juwayriyya.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا قَبِيصَةُ، قَالَ: حَدَّثَنَا سُفْيَانُ، عَنْ مُحَمَّدِ بْنِ عَبْدِ الرَّحْمَنِ مَوْلَى آلِ طَلْحَةَ، عَنْ كُرَيْبٍ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ اسْمَ جُوَيْرِيَةَ كَانَ بَرَّةَ، فَسَمَّاهَا النَّبِيُّ صلى الله عليه وسلم جُوَيْرِيَةَ.
sunnah.com