Charles Ellicott Commentary 1 Chronicles 2:9

"The sons also of Hezron, that were born unto him: Jerahmeel, and Ram, and Chelubai." — 1 Chronicles 2:9 (ASV)

Jerahmeel. — God pities.

Ram. — Called Aram in our Lord’s genealogy (Matthew 1:0). The two names are synonyms, both meaning high, and are used interchangeably in Job 32:2 (Ram) and Genesis 22:21 (Aram).

Chelubai. — Strictly, the Chelubite or Calebite, a gentilic term formed from Caleb (1 Chronicles 2:18). This seems to show that we are concerned here not so much with individual sons of Hezron as with families or clans of Hezronites.