Cases of word usage

1) an apparatus for reducing speed or stopping motion e.g. of a bicycle, vehicle etc (brake)

2) at a dangerously fast speed (breakneck)

3) to hold, speed up, the progress of (a plan, business etc) (expedite)

4) (of) 50; (of a temperature, speed etc) between 50 and 59 (fifty)

5) (of) 40; in the forties = (of a temperature, speed etc) between 40 and 49 (forty)

6) a person who governs a province or (in US) a State; an apparatus that regulates the speed of ship's engine revolutions (governor)

7) to move or act with speed (hasten)

8) (also Mach number) the ratio of the air speed of an aircraft to the speed of sound (mach)

9) an instrument used to give the speed for playing music (metronome)

10) in the middle (of a length, distance, speed etc) (midway)