Webster's Revised Unabridged Dictionary · 1913

Depolarize

Depolarize , transitive verb

[Prefix de- + polarize: compare French dépolarizer.]

1.
(Optics) To deprive of polarity; to reduce to an unpolarized condition.

This word has been inaccurately applied in optics to describe the effect of a polarizing medium, as a crystalline plate, in causing the reappearance of a ray, in consequence of a change in its plane of polarization, which previously to the change was intercepted by the analyzer.

2.
(Electricity) To free from polarization, as the negative plate of the voltaic battery.