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

Tooth and nail didn’t seem to do the Coliseum League title game justice on Friday night.

From Los Angeles Times • Oct. 25, 2025

Tooth and nail might be a cliché, but these kids Rams are showing plenty of teeth amid the relentlessness of a, well, nail.

From Los Angeles Times • Sep. 17, 2023

Tooth and nail Polly contested every inch of ground.

From The Town Traveller by Gissing, George

Tooth and nail, my dear fellow," he said, gayly; "foot, horse, and dragoons!

From Cardigan by Chambers, Robert W. (Robert William)

Tooth and nail she resented the proposed changes; and among the malcontents there figured a soldier Pomeroy, now head of his house, who had fought with distinction in France during the reign of Henry VIII.

From A West Country Pilgrimage by Phillpots, Eden