The most common and most likely answer to this crossword clue is the 6 letter word ACINUS
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Buddy explains!
The straight part
We know that "the pip!" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case the pip! = acinus.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 ACINUS mean?
ACINUS noun- One of the small grains or drupelets which make up some kinds of fruit, as the blackberry, raspberry, etc.
- A grape-stone.
- One of the granular masses which constitute a racemose or compound gland, as the pancreas; also, one of the saccular recesses in the lobules of a racemose gland.