The most common and most likely answer to this crossword clue is the 7 letter word CONCORD
I've seen this crossword clue in Financial Times
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More clues leading to the result CONCORD
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The straight part
We know that "agreement" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case agreement = concord.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 CONCORD mean?
CONCORD noun- A state of agreement; harmony; union.
- Agreement by stipulation; compact; covenant; treaty or league
- (grammar) Agreement of words with one another, in gender, number, person or case.
- An agreement between the parties to a fine of land in reference to the manner in which it should pass, being an acknowledgment that the land in question belonged to the complainant. See fine.
- (probably influenced by chord) An agreeable combination of tones simultaneously heard; a consonant chord; consonance; harmony.
- A variety of sweet American grape, with large dark blue (almost black) grapes in compact clusters; a Concord grape.
- To agree; to act together