to break or cause something to break with a sudden sound, often forming lines or pieces
He cracked the egg into the bowl.
The ice cracked beneath our feet.
to find the answer to something difficult, such as a problem, code, or mystery
Scientists finally cracked the genetic code.
Can you crack the password for me?
to lose self-control or become unable to cope under pressure or stress
After days without sleep, he cracked during the interrogation.
She tried to stay calm, but eventually cracked and began to cry.
