Standard used by many European states (9)

I believe the answer is:

tricolour

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'standard' is the definition.
(I know that tricolour is a type of standard)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for tricolour that I've seen before include "Standard of French perhaps" , "French national flag" , "Having or involving three colours" .)

I've seen this clue in The Telegraph.

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