Learn the idiom: A Hard Nut to Crack

An illustration of a confused squirrel depicting the idiom "a hard nut to crack" with the definition and an example: Determining how many acorns he needed for winter was a hard nut to crack.

A hard nut to crack (idiom)

Look at the picture and try to guess the meaning of the idiom 'a hard nut to crack.'

A hard nut to crack:

(1) a problem or situation that's difficult to solve or deal with;

(2) a person who is difficult to understand or know;

(3) a group, place or opportunity that's difficult to join or gain entry.

Notes

Before we move on, you know what a "nut" is, right?

If not, the animal (a squirrel) in the image above is holding a nut. Squirrels can crack open nuts using their strong, sharp teeth. Humans, on the other hand, would probably crack their teeth trying to do the same.

This idiom likely comes from the fact that many nuts, like walnuts or hazelnuts, have hard shells that require a nutcracker—or a lot of effort—to break open. Similarly, a "hard nut to crack" refers to something that takes effort or persistence to solve.

The idiom has been used in English since at least the 18th century to describe challenges, difficult people, or complex problems.

Sentence examples

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— This algebra equation sure is a hard nut to crack.

— Congratulations on restoring your antique car—I'll bet that was a hard nut to crack.

— Climbing Mount Kilimanjaro is a hard nut to crack.

— Jennifer is a hard nut to crack. One day she's friendly and the next she's super quiet, so I'm not sure if she likes me or not.

— My new secretary is a hard nut to crack. I'm not sure if she's unhappy here, just a shy person or if she's bored.

— A number of women have become leaders in business but the majority still find getting upper management positions a hard nut to crack.

— We've had a lot of success with our retail stores but we're finding that selling our product online is a hard nut to crack.

— With your skills, getting a tennis scholarship to a university is possible but the professional tour will be a hard nut for you to crack.

— Getting a membership into that country club is a hard nut to crack for minorities so don't be surprised if your application is not approved.

Here are some MORE sentence examples. The more the better, right?

— The detective said the case was a hard nut to crack, but she eventually solved it.

— Despite their efforts, they couldn’t crack the code—it was just too hard a nut to crack.

— This new client is incredibly skeptical. She's going to be a hard nut to crack, but we’re determined to try.

— If you think the midterm exam was easy, just wait for the final exam—it’ll be a real hard nut to crack.

— Don’t give up just because it’s a hard nut to crack! Keep pushing forward.

— Well of course the director is going to be a hard nut to crack, but I’ll do my best to get her on board.

— We’re finding out that managing a remote team is a hard nut to crack.

— The mystery was a hard nut to crack, but it was finally resolved after months of investigation.

— Wow, that riddle is a hard nut to crack!

— Why does solving this puzzle always feel like such a hard nut to crack?

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Synonyms

a tough nut to crack
a tough/hard row to hoe