(law) The duty of a party in a legal proceeding to prove an assertion of fact; it includes both the burden of production and the burden of persuasion; the onus probandi.

Alternative spelling of bulletproof (Capable of withstanding a direct shot, reliable, or unbreakable).

(rare, software engineering) proof of concept; pilot project

Designed and constructed to withstand or minimize damage from an internal or external explosion.

(logic) The indirect verification or falsification of a statement by the verification or falsification of each of the finite number of cases which arise therefrom.

plural of proof by exhaustion

(law) Of a person whom a judgment cannot be enforced against.

A person who reads proof, copy or other text, looking for errors and making corrections

airtight

A fallacious judgment that, because a premise cannot be proven true, that premise must be false.