tooth and nail

American  

adverb

1. with all one's resources or energy; fiercely.

   We fought tooth and nail but lost.

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tooth and nail Cultural  

1. To fight “tooth and nail” is to fight with the intensity and ferocity of a wild animal: “The resistance forces fought the invading troops tooth and nail.”

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Etymology

Origin of tooth and nail

First recorded in 1525–35

Example Sentences

"We will fight this tooth and nail," Das said.

From Barron's • Mar. 24, 2026

She has said she will “fight tooth and nail against any effort to further roll back these fundamental protections.”

From Slate • Mar. 17, 2026

ConocoPhillips is the country’s largest nonsovereign creditor and has been fighting tooth and nail to recoup the roughly $12 billion it is still owed.

From The Wall Street Journal • Jan. 19, 2026

“We fought tooth and nail to retain those benefits,” said Williams, who is president of UMW Local 1188 in Coshocton County, in central Ohio’s Appalachian region.

From Salon • Aug. 27, 2025

It was also a victory for Avery Brundage, president of the American Olympic Committee, and his allies who had fought tooth and nail to ensure that there was no boycott.

From "The Boys in the Boat: Nine Americans and Their Epic Quest for Gold at the 1936 Berlin Olympics" by Daniel James Brown