Of any system where all gains are offset by exactly equal losses.

(physics, quantum mechanics) The lowest possible energy of a given quantum mechanical system.

The strict policy of enforcing all the laws of a state, or the rules of an institution, and allowing no toleration or compromise even for first-time offenders or petty violations.

(game theory) A game (or a similar political or economic system) in which the gains of some players must equal the losses of others.

(chiefly Britain) subject to no value-added tax when sold (but the supplier can still recover VAT attributable to it)

simple past tense and past participle of zero-rate

Originally, the point on the land or water surface below which a nuclear bomb detonates in the air; now also the point on such a surface at or above the detonation.

(of a temperature) below 0°C; freezing cold

To focus one's aim; to zoom in and center (on something). / To successfully narrow down a search (for). / To concentrate or focus one's attention (on a task). / (idiomatic) To converge (on).

A bicultural name for New Zealand.