The most common and most likely answer to this crossword clue is the 13 letter word ANACHRONISTIC
I've seen this crossword clue in Independent
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More clues leading to the result ANACHRONISTIC
- Thracian coins misrepresented as belonging to another time
- Lark about rattling chains or being out of time
- Account including Corinthianssadly no longer seen as relevant
- Isn’t archaic? No, becoming out of date
- Anarchist icon destroyed before its time
- Non-archaic, it's possibly ahead of its time!
- Broken chair contains something old
Buddy explains!
The straight part
We know that "no longer seen as relevant" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case no longer seen as relevant = anachronistic.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 ANACHRONISTIC mean?
ANACHRONISTIC adjective- Erroneous in date; containing an anachronism; in a wrong time; not applicable to or not appropriate for the time.
- (of a person) Having opinions from the past; preferring things or values of the past; behind the times; overly conservative.