Lewis is the highest-rated inside linebacker in the 2021 class.
The Terps also secured wide receiver Marcus Fleming as a transfer from Nebraska.
The recruiting class is led by four-star linebacker Demeioun Robinson.
The junior wide receiver leads the Terps in receptions, receiving yards and touchdowns this season.
Taulia Tagovailoa threw three interceptions in the loss.
The Terps face No. 12 Indiana on Saturday for their first game in three weeks.
The home opener will be Oct. 31 against Minnesota.
The first weekend of the 2020 NFL season saw multiple Terps make an impact on the field.
Trader Jr. is a five-star lacrosse recruit and a three-star football recruit.
The Big Ten halted play Tuesday, but it left open the possibility of conducting a spring season.