The most common and most likely answer to this crossword clue is the 5 plus 4 letter word GRAND SLAM
I've seen this crossword clue in Financial Times
G
R
A
N
D
S
L
A
M
More clues leading to the result GRAND SLAM
- After fine, slate major championship
- Piano’s not entirely inadequate, winning all the trophies
- Fifty hosted by wonderful boy, full house on the cards?
- Dolled up, appropriating money for sporting achievement
- Garlands thrown over man’s head for rare sporting achievement
- Ms Garland beaten in top score at the bridge table
- Nan and mother, squeezing first of sponges, left wiping the floor with the others
- Thousands go on strike in major event
- Noble to slate bridge contract
- Achievement of one who doesn’t miss a trick
Buddy explains!
The straight part
We know that "major event" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case major event = grand slam.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.