What is the acronym in BASE jumping?

Search: base jump

Why: On the info for Dateline:

Hoda Kotb recounts 10 harrowing near-death moments captured by camera. Included: a failed BASE jump; and a rooftop fire rescue.

Answer: The acronym stands for the 4 types of surfaces from which one can jump:

• Building
• Antenna
• Span
• Earth
  

Source: HowStuffWorks

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