First empire smashed by resistance (7)

I believe the answer is:

premier

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'first' is the definition.
(similar in meaning)

I can't explain the rest of the clue.

(Other definitions for premier that I've seen before include "Leading" , "Foremost" , "Which is having precedence" , "Prime minister" , "First (minister)" .)

I've seen this clue in The Sun.

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