dead set against

Idioms  

1. Completely opposed to, as in His parents were dead set against John's taking a year off from college. Set against has been used to mean “opposed to” since the 1400s. Dead acquired the meaning “utterly” in the 16th century.

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Example Sentences

With Poland dead set against it, that means either France or Italy, both home to rowdy agricultural lobbies, would have to sign on.

From Barron's • Dec. 30, 2025

“There were some colleagues that were dead set against it, saying they would never help China learn our technology,” said one magnet expert who ultimately agreed to go to China.

From The Wall Street Journal • Oct. 20, 2025

To the north, Nicholas II of Russia had just put down a revolution in 1905 and was dead set against similar unrest on his southern border with Iran.

From Los Angeles Times • Nov. 10, 2022

You don't want jurors who are dead set against you and supporting the opposition.

From Salon • Sep. 19, 2022

"Why are you so dead set against it, I wonder?"

From "The Inquisitor's Tale" by Adam Gidwitz