desperately; with all one's might; like crazy
Expresses doing something with extreme effort, as if one's life depended on it. Often used in casual or emphatic speech.
I studied like crazy to pass the exam.
He ran desperately and barely caught the last train.
Phrase composed of 死ぬ (to die) + 気 (spirit, feeling) + で (particle indicating manner). Literally 'with the feeling of dying', used idiomatically to mean 'desperately'.