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

See Examples For:

tooth and nail

And at O’Hare International Airport, American Airlines has been fighting tooth and nail not to lose access to gates in its terminal because of the Chicago hub’s potential to fuel its credit-card loyalty program.

From The Wall Street Journal ● Jul. 17, 2026

"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

I'd fought tooth and nail to keep him and, back fit again, he was tearing us up the table in what is now League One, scoring some spectacular goals.

From BBC ● Feb. 2, 2026

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