Prince ____ III of Monaco was the husband of Grace Kelly (7)

I believe the answer is:

rainier

(Other definitions for rainier that I've seen before include "weather getting worse" , "Volcano in Washington" , "more drops?" , "This is more likely to pour down" , "Prince of Monaco, married to Grace Kelly, d. 2005" .)

I've seen this clue in The Times and The Sunday Times.

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