Decelerated (6)
(Other definitions for braked that I've seen before include "slowed down" , "Brought car to a halt" , "Halted" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">decelerated</span>' is the definition.<br/ ><span class="explanation-format__explanation">(slowing is a kind of decelerating)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for slowed that I've seen before include "Braked" , "Applied the brakes" , "Reduced speed" , "Decelerated" .)