The most common and most likely answer to this crossword clue is the 7 letter word SUMMONS
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The straight part
We know that "order" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case order = summons.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 SUMMONS mean?
SUMMONS noun- A call to do something, especially to come.
- A notice summoning someone to appear in court, as a defendant, juror or witness.
- A demand for surrender.
- To serve someone with a summons.
- To call people together; to convene.
- To ask someone to come; to send for.
- To order (goods) and have delivered
- To rouse oneself to exert a skill.
- To call a resource by magic.
- To summons; convene.