The most common and most likely answer to this crossword clue is the 8 letter word KNEEJERK
I've seen this crossword clue in The Times
K
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E
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J
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Buddy explains!
The straight part
We know that "Predictable" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case predictable = kneejerk.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 KNEEJERK mean?
KNEEJERK noun- A sudden reflexive movement of the leg below the knee, as a reaction to a tap to the tendon just below the patella (kneecap).
- Unthinking, not carefully considered, (nearly) automatic, spontaneous, easily predictable