sha.man describes becoming fat in accounts of abundance and, of a people's heart, being made fat so that understanding is blocked.

The attested use chiefly concerns people becoming fat in contexts of satisfaction, abundance, or prosperity; Isaiah 6:10 applies the expression to the heart in an instruction that also closes ears and obscures eyes.

1. Becoming fat amid abundance or satisfaction · dominant

   In Deuteronomy 32:15, Qal forms occur as Jeshurun and then “you” become fat, thicken, and are sated before abandoning God. In Jeremiah 5:28 the Qal perfect describes people who “have grown fat” while failing to judge for the orphan and needy; in Nehemiah 9:25, after eating and being satisfied amid abundant provisions, the APB renders the Hiphil sequential form “grew fat.”

   Deuteronomy 32:15Jeremiah 5:28Nehemiah 9:25
2. Making the heart fat · rare

   In Isaiah 6:10, the Hiphil imperative directs that the people's heart be made fat, together with making their ears heavy and smearing their eyes; the stated result is that they do not see, hear, understand, turn, and be healed. The APB renders the clause “Make the heart of this people fat.”

   Isaiah 6:10

In the Anselm Project Bible: The APB presents the term as “grew fat” or “have grown fat” in the abundance and conduct passages, and as “Make the heart of this people fat” in Isaiah 6:10. These renderings confirm the clauses' overall presentation rather than a fixed English equivalent.