Genesis 38:29

29But as he drew back his hand, behold, his brother came out. And she said, “What a breach you have made for yourself!” Therefore his name was called aPerez.
 Perez means a breach

Numbers 26:20

20And the sons of Judah according to their clans were: of Shelah, the clan of the Shelanites; of Perez, the clan of the Perezites; of Zerah, the clan of the Zerahites.
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