tooth and nail

American

adverb

with all one's resources or energy; fiercely.

We fought tooth and nail but lost.

tooth and nail Cultural

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.”

Etymology

Origin of tooth and nail

First recorded in 1525–35

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"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

But according to Ms Skinner's lawyer, all the high-value complex claims are being fought "tooth and nail".

From BBC • Sep. 28, 2025

Meanwhile Madame Maxime was trying to restrain Fleur Delacour, who was quite hysterical, fighting tooth and nail to return to the water.

From "Harry Potter And The Goblet Of Fire" by J. K. Rowling

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023