Ruled measure government introduced must be reversed (7)

I believe the answer is:

reigned

I'm a little stuck... Click here to teach me more about this clue!

'ruled' is the definition.
(reigning is a kind of ruling)

I can't explain the remainder of the clue.

(Other definitions for reigned that I've seen before include "Had sovereign power" , "Was king" , "Held sway" , "Ruled" , "Was monarch" .)

I've seen this clue in The Guardian.

Want a hint initially instead of a full solution? Install my app