Compensation earned by remaining on a team’s roster on a certain date. Roster bonuses count in full against the salary cap in the season in which they are earned, unless fully guaranteed at signing. They are used to avoid signing-bonus proration, which pushes dead money into the future.
However, they released the All-Pro running back before a a 2021 roster bonus–worth $5 million–became fully guaranteed on March 20, 2020. His non-guaranteed $5.5 million 2020 base salary also also would have become fully guaranteed on that date.
Largest roster bonus in 2020: Jared Goff ($21.0 million with the Rams).