tsa.lal describes those covered by the sea sinking like lead in the great waters.

The attested use depicts a group going down after the sea covers them, likened in the verse to lead sinking in great waters.

1. Going down beneath covering waters · dominant

   In Exodus 15:10, the Qal perfect third common plural form describes those whom the sea covered going down; the APB renders the clause, “they sank like lead in the great waters.”

   Exodus 15:10

In the Anselm Project Bible: In Exodus 15:10, the APB presents the action with “they sank like lead in the great waters.” This rendering confirms the clause's scene rather than isolating every contribution of the Hebrew form.