1) Applies the brakes 2) Approaches a red light 3) Brakes 4) Cuts the engine 5) Cuts the speed 6) Decelerates 7) Decreases speed 8) Delays 9) Does some rubbernecking 10) Eases up on the gas 11) Enters a school zone 12) Hits the brakes 13) Loses momentum 14) Loses steam 15) Loses velocity 16) Opposite of hastens 1) Retards 2) Stems 
• (n.) Milk sickness.
Slows noun (Medicine) Milk sickness.