da.gah describes the hoped-for great increase of the boys in the land.

The sole attested use expresses a wish that the boys would increase greatly in the midst of the land.

1. Increase greatly as a blessing · dominant

   In Genesis 48:16, the Qal imperfect third masculine plural form occurs in a blessing for the boys, following the wish that the angel bless them; the APB renders the clause, “and may they multiply greatly in the midst of the land.”

   Genesis 48:16

In the Anselm Project Bible: In Genesis 48:16, the APB presents the clause as “may they multiply greatly in the midst of the land.” Its wording confirms the clause's overall sense rather than isolating each term.