The most common and most likely answer to this crossword clue is the 8 letter word ALMANACS
I've seen this crossword clue in The Daily Telegraph
A
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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 ALMANACS mean?
ALMANACS noun- A book or table listing nautical, astronomical, astrological or other events for the year; sometimes, but not essentially, containing historical and statistical information.
- A handbook, typically published annually, containing information on a particular subject
- A GPS signal consisting of coarse orbit and status information for each satellite in the constellation.