1. What does it mean?
벼락치기 means doing a lot of preparation in a short burst just before it is needed. It is especially familiar for last-minute exam study but can describe hurried preparation for another task.
Also written or said as byeorakchigi
2. The nuance
It describes timing and intensity, not a guaranteed learning method. Someone can joke about 벼락치기 while recognizing they would prefer a steadier routine.
3. Examples
“시험 전날 벼락치기하느라 늦게 잤어.”
I stayed up late cramming the night before the exam.
“이번 발표는 벼락치기 안 하려고 미리 시작했어.”
I started this presentation early to avoid a last-minute rush.
Sources
References support the meaning and usage. Example sentences are written for NoCapWiki.