To explode or cause to explode. The demolition team will blow up the old building tomorrow.
To inflate or fill with air or gas. Please blow up the balloons for the party.
To become very angry or lose one's temper. He tends to blow up whenever someone criticizes his work.
To enlarge a photograph or image. Can you blow up this picture so we can see the details better?
To exaggerate or make something seem more important than it is. The media tends to blow up minor incidents to attract more viewers.