The most common and most likely answer to this crossword clue is the 8 letter word OBLIVION
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More clues leading to the result OBLIVION
- Old boy mostly existing with love in limbo
- Forgetfulness leads to our best violin being shattered
- Ignorance of Bach’s first violin playing
- Limbo dancing boy with violin – bar wobbly at the end
- Died with violin play and forgetfulness
- Forgetfulness leads to our best violin being smashedsmashed {sic}
- Neglected state of old black cat that’s fed six
- Double vision could result from rum used with such forgetfulness
- Died, not quite alive, having nothing in extinction
- International no 6 must get into shape needing trim — recall could be hindered by it?
Buddy explains!

The straight part
We know that "extinction" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case extinction = oblivion.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 OBLIVION mean?
OBLIVION noun- The state of forgetting completely, of being oblivious, unconscious, unaware, as when sleeping, drunk, or dead.
- The state of being completely forgotten, of being reduced to a state of non-existence, extinction, or nothingness, incl. through war and destruction. (Figuratively) for an area like hell, a wasteland.
- Amnesty.
- To consign to oblivion; to efface utterly.