The most common and most likely answer to this crossword clue is the 7 letter word TRIUMPH
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More clues leading to the result TRIUMPH
- Badly hurt, I'm carrying piano - a great achievement!
- Hit Republican leader hard around lunchtime?
- . Leader of Israel contributed to President Bush’s ultimate victory
- Hard to support narcissistic politician with ego in victory
- Start of impeachment interrupting president at height of success
- One featured in president Hoover’s first victory
- Success, as better bandages beginning to improve health at first
- The speaker involved in President Hoover’s first victory
- Cap worn by Peto before Henry’s victory
- Success whipped up mirth
Buddy explains!

The straight part
We know that "a great achievement" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a great achievement = triumph.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.
What does TRIUMPH mean?
TRIUMPH noun- A conclusive success following an effort, conflict, or confrontation of obstacles; victory; conquest.
- A magnificent and imposing ceremonial performed in honor of a victor.
- Any triumphal procession; a pompous exhibition; a stately show or pageant.
- A state of joy or exultation at success.
- A trump card.
- A card game, also called trump.
- A ceremony held to publicly celebrate and sanctify the military achievement of an army commander.
- A work of art, cuisine, etc. of very high quality.
- To celebrate victory with pomp; to rejoice over success; to exult in an advantage gained; to exhibit exultation.
- To prevail over rivals, challenges, or difficulties.
- To succeed, win, or attain ascendancy.
- To be prosperous; to flourish.
- To play a trump in a card game.