Fausset's Bible Dictionary 
Perez "breach" because he broke forth from the womb before his twin brother Zarah who had first put out his hand. Son of Judah and Tamar his daughter in law ( Matthew 1:3; Luke 3:33; Genesis 38:29). His house retained the primogeniture; it was famous for being prolific, so as to pass into a proverb ( Ruth 4:12; Ruth 4:18-22). After the deaths of Er and Onan childless, Pharez took the rank of Judah's son, next after Shelah. His sons Hezron and Hamul became heads of two new chief houses. Hezron was forefather of David and Messiah. Caleb's house too was incorporated into Hezron's.
Under David "the chief of all the captains of the host for the first month was of the children of Pharez" ( 1 Chronicles 27:2-3), famed for valor ( 1 Chronicles 11:11. (See Jashobeam .) 2 Samuel 23:8). Hezron married a second time Muchir's daughter; so one line of Pharez's descendents reckoned as sons of Manasseh. Pharez's house was the greatest of the houses of Judah; 468 valiant men of the children of Pharez alone of Judah dwelt in Jerusalem ( Nehemiah 11:3-6; 1 Chronicles 9:3-6) after the return from Babylon.
Smith's Bible Dictionary 
Pha'rez. (Perez, 1 Chronicles 27:3; Phares, Matthew 1:3; Luke 3:33 1 Esdras 5:6. Twin son, with Zarah or Zerah, of Judah and Tamer, his daughter-in-law. (B.C. 1730). The circumstances of his birth are detailed in Genesis 38.
Pharez occupied the rank of Judah's second son, and from two of his sons, sprang two new chief houses, those of the Hezronites and Hamulites. From Hezron's second son, Ram, or Aram, sprang David and the kings of Judah, and eventually Jesus Christ . In the reign of David, the house of Pharez seems to have been eminently distinguished. See Perez; Phares .
Holman Bible Dictionary 
Genesis 38:29 Genesis 46:12 Numbers 26:20-21 Ruth 4:12 4:18 1 Chronicles 2:4-5 1 Chronicles 4:1 1 Chronicles 9:4
Hawker's Poor Man's Concordance And Dictionary 
Son of Judah, by Tamar, ( Genesis 38:29) The word is translated in the margin of the Bible a breach. The same word as David afterwards used from the breach made at Uzzah's touching the ark. ( 2 Samuel 6:8)
Easton's Bible Dictionary 
Genesis 38:29 Ruth 4:18-22 1 Chronicles 27:3 Matthew 1:3
International Standard Bible Encyclopedia 
fā´rēz (King James Version 1 Esdras 5:9; 8:30): The same as Revised Version Phoros (which see).