1 A corruption of "bombproof" meaning very secure.

2 Bombproof - A hold or anchor that is thought to offer the utmost security; for example, a top-rope anchor around a large, stable tree trunk or immovable boulder.

3 Aerogel is also being tested for future bombproof housing and armour for military vehicles.

4 Grade I A short climb close to the road with bombproof belays and an easy descent.

5 Belays: The belays are mostly shiny bolts and are all bombproof . They can be used to rap down the route in need (some belays are used only for rapping, some belong also to the climbing route).

6 Used to indicate that something is exceptionally solid, e . g . an anchor, a hold . See also bombproof.

7 A mountain range bristling with antennas harbors a maze of bombproof underground arsenals and shelters served by a tunnel 4km long.