### Clue: Thousands go on strike in major event (5,4)
### Answer: GRAND SLAM 
 ### Explanation: Definition: major event
  GRANDS(plural of grand,thousand in number, especially dollars or pounds) ***placed above***(go on, in a down clue) LAM(hit,strike)
Defn: The achievement,major event in sports like golf or tennis where a player wins in a single year all the major events (including the British Open in golf, or Wimbledon in tennis) in that sport.