What is another word for tough nut to crack?
Pronunciation: [tˈʌf nˈʌt tə kɹˈak] (IPA) 
When it comes to describing a difficult problem or a person who is hard to understand, the phrase "tough nut to crack" is commonly used. However, there are a variety of synonyms that can be used to convey similar meaning. "Hard nut to crack", "challenging puzzle", "formidable obstacle", "daunting challenge", "knotty problem", and "complex enigma" are some of the examples. These phrases emphasize the difficulty of the problem or person in question, and suggest that it will require extra effort, skill, and persistence to overcome the challenge. By using such synonyms, one can add color and depth to their language, making their writing or conversation more engaging.
