To make a solution neutral (neither acidic nor basic, pH of 7) by adding a base to an acidic solution, or an acid to a basic solution.

To nullify oscillation-producing voltage feedback from the output to the input of an amplifier through tube interelectrode capacitances; an external feedback path is used to produce at the input a voltage that is equal in magnitude but opposite in phase to that fed back through the interelectrode capacitance.

To place a lens in contact with other lenses of equal and opposite power so that the combination has zero power.

1. To destroy or reduce the effectiveness of enemy personnel and materiel by gunfire, bombing, or any other means.

2. To make a toxic chemical agent harmless by chemical action.

3. To disarm or otherwise render safe a mine, bomb, missile, or booby trap.