The most common and most likely answer to this crossword clue is the 8 letter word TARDIEST
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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 TARDIEST mean?
TARDIEST adjective- Late; overdue or delayed.
- Moving with a slow pace or motion; not swift.
- Ineffectual; slow-witted, slow to act, or dull.
- Unwary; unready (especially in the phrase take (someone) tardy).
- Criminal; guilty.