Polarizability

Part of speech: noun

Definitions

1. The capacity of a substance to undergo polarization when subjected to an electric field, indicating how much its electron cloud can be distorted
2. The degree to which a material can become polarized under the influence of an external electric field, reflecting the ease of electron cloud displacement
3. A measurement of how easily a material's charge distribution shifts in response to an external electric field, influencing its interactions with light and other electromagnetic waves

Etymology: Polarizability is a plain technical formation: "polarize" with the suffix "-ability" added, and the whole thing is a modern scientific coinage rather than an ancient word. The base verb "polarize" comes from "polar," which traces back to the Greek word for the axis or pole of the sky, and the sense of making something "polarized" in the physics of light came later, once that terminology was applied to electric and magnetic effects. The suffix does most of the work. "-ability" descends from Latin "-abilitas," the noun form of "-abilis," meaning "able to be" something. It passed into English through Middle French, where "-able" and "-abilité" were common, and English then attached "-ability" to a huge range of verbs. A word like polarizability simply asks whether the thing can be acted on in that way, here whether its electron cloud can be pushed out of its resting position by an external field.