Cryptic crossword clue
US magazine was illuminating about one month deadline 4-5

The most common and most likely answer to this crossword clue is the 10 letter word TIME-LIMIT

I've seen this crossword clue in The Times
T
I
M
E
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L
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M
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T

Buddy explains!

The straight part
We know that "deadline" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case deadline = time-limit.
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 TIME-LIMIT mean?

TIME-LIMIT noun
  1. A time by which something must finish
  2. A duration beyond which something may not exceed
TIME-LIMIT verb
  1. To set a time limit on.

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