The most common and most likely answer to this crossword clue is the 8 letter word CELERITY
I've seen this crossword clue in The Daily Telegraph
C
E
L
E
R
I
T
Y
More clues leading to the result CELERITY
- Expedition finding that thing in green
- Speed star Bullock’s first to leave
- Rapidity with which star dismisses bishop
- Heartless superstar gets speed
- Speed shown by reality TV winner releasing book
- Heartless name for speed
- Expedition to see David Beckham, for example, with centre parting?
- Heartless person who’s well known for speed
- Speed – it’s required between the sticks
- Part of salad — pop it in for quickness
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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 CELERITY mean?
CELERITY noun- Speed, swiftness.
- The speed of individual waves (as opposed to the speed of groups of waves).
- The speed with which a perturbation to the flow propagates through the flow domain.
- The speed of symbol transmission, now called baud rate.