The most common and most likely answer to this crossword clue is the 7 letter word CAUDATE
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The straight part
We know that "Tailed" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tailed = caudate.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 CAUDATE mean?
CAUDATE noun- Any member of the Caudata order of amphibians.
- Tapering into a long, tail-like extension at the apex.
- Having a tail.
- Of or pertaining to the Caudata order of amphibians.
- Indicates an anatomical structure with a tail-like extension, such as the Caudate nucleus.