Zaynab's name was originally Barrah, but it was said that this name implied she was praising her own purity, so the Messenger of Allah ﷺ renamed her Zaynab.
Azami 14506
Sahih
عن أبي هريرة
أن زينب كان اسمها برة، فقيل: تزكي نفسها، فسماها رسول الله ﷺ زينب.
Bukhari related it in Adab (6192), and Muslim in Adab (2141), both through Muhammad bin Jafar, from Shuba, from Ata bin Abu Maymuna, from Abu Rafi, from Abu Hurairah, who narrated it.