Idiom: to bomb something



Context #1:
Jim: How did you do on the History final exam yesterday?
Chuck: Actually, I think I bombed it!  I didn’t study at all.
Jim: What were you thinking? That exam is like one quarter of our overall grade.

Context #2:
Sally: Can you help me study for the Geometry exam that we have next week?
Cathy: Sure! 
Sally: I am having a hard time in this class and I don’t want to bomb the exam.
Cathy: No problem.  Let’s meet at Starbucks tonight and I’ll help you with it.

Meaning: «to bomb something» means to totally fail. It is most often used in an educational context, but it can also be used for such things like job interviews and projects. 

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