The most common and most likely answer to this crossword clue is the 6 letter word DIGEST
I've seen this crossword clue in The Times
D
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More clues leading to the result DIGEST
- Summary of archaeological activity is in French
- Fail to make joke, say, for periodical
- Take in synopsis
- Process like the litmus test ends
- Girton's top dons reach conclusion on blessed fellow’s summary
- Take in selected news items?
- Like time in Washington DC in summary
- Detective gets rough synopsis
- Summary gets amended after papers reviewed
- Study comes to an end, keeping good time
Buddy explains!

The straight part
We know that "periodical" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case periodical = digest.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 DIGEST mean?
DIGEST verb- To distribute or arrange methodically; to work over and classify; to reduce to portions for ready use or application.
- To separate (the food) in its passage through the alimentary canal into the nutritive and nonnutritive elements; to prepare, by the action of the digestive juices, for conversion into blood; to convert into chyme.
- To think over and arrange methodically in the mind; to reduce to a plan or method; to receive in the mind and consider carefully; to get an understanding of; to comprehend.
- To bear comfortably or patiently; to be reconciled to; to brook.
- To expose to a gentle heat in a boiler or matrass, as a preparation for chemical operations.
- To undergo digestion.
- To suppurate; to generate pus, as an ulcer.
- To cause to suppurate, or generate pus, as an ulcer or wound.
- To ripen; to mature.
- To quieten or reduce (a negative feeling, such as anger or grief)
- That which is digested; especially, that which is worked over, classified, and arranged under proper heads or titles
- A compilation of statutes or decisions analytically arranged; a summary of laws.
- Any collection of articles, as an Internet mailing list including a week's postings, or a magazine arranging a collection of writings.
- The result of applying a hash function to a message.