The most common and most likely answer to this crossword clue is the 6 letter word DECKLE
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The straight part
We know that "Paper’s edge" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case paper’s edge = deckle.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 DECKLE mean?
DECKLE noun- (paper-making) A frame or edge which limits the pulp and, consequently, the size of the resulting paper.
- A membrane covering the outermost side of a brisket of beef, where it was attached to the rib cage
- (Jewish cuisine) The fattier, smaller point-cut portion of a brisket of beef, being the superficial pectoral muscle.