a hard/tough nut (to crack)

noun phrase

: a person or thing that is difficult to deal with, understand, or influence

The team's defense is a tough nut to crack.

The problem is a hard nut to crack.

He's a tough nut, but I think I can get him to agree to the contract.

Examples of a hard/tough nut (to crack) in a Sentence

Recent Examples on the Web

The largest shale play outside North America has proven to be a tough nut to crack over the last decade. —David Blackmon, Forbes, 4 Sep. 2024

Is there any possible redemption for Kreese? Heald: There’s always a possibility, but Kreese is a tough nut to crack. —Selena Kuznikov, Variety, 19 July 2024

But the Riemann hypothesis is a tough nut to crack. —Manon Bischoff, Scientific American, 1 July 2024

As the most mysterious of the three amateur detectives/podcasters at the center of Only Murders in the Building, Mabel (Selena Gomez) is initially a tough nut to crack. —Marcus Jones, EW.com, 24 Feb. 2022

There are many other types of oaks to love, and telling them apart can be a tough nut to crack. —Mark Gozonsky, Los Angeles Times, 1 June 2023

For organizations layered in functional metrics and driving a cost agenda, this is a tough nut to crack. —Lora Cecere, Forbes, 19 Apr. 2023

The military is always a hard nut to crack, as many of us know from working in journalism over the years, and in this case, for example, the defendants were under a gag order not to talk. —San Diego Union-Tribune, 18 Nov. 2022

Until recently, his home base of Brussels had been a tough nut to crack. —Sarah Medford, WSJ, 4 Mar. 2022