The answer is Demeatrice. Lamar's full name is Lamar Demeatrice Johnson. It's worth noting that different sources may provide variations in the spelling of his middle name, some sources spell it as "Demontrious" instead of "Demeatrice". Regardless, both variations refer to the same person - Lamar Johnson.
The Lamar Jackson Challenge: Test Your Knowledge on the Dynamic Dual-Threat Quarterback!