1) the ability to understand quickly and clearly (acumen)

2) moving, acting, quickly and easily (agile)

3) a continuous low sound made by parts of machines that turn quickly (burr)

4) to cause people to move quickly and excitedly (bustle)

5) (the sound of) people talking quickly and informally together (chatter)

6) angry; easily or quickly showing anger (cross)

7) (of prices, levels of unemployment, number of people opposing something etc) to increase quickly (escalate)

8) acting quickly and efficiently (expeditious)

9) a thin coating or covering; a series of photographs that is shown quickly on a screen so that the people, objects etc in them appear to be moving (film)

10) likely to burst into flames and to burn quickly (flammable)