quantum Definition

quantum
noun quanta

1a. An amount or quantity, especially a specified one;
1b. A portion, part or share.
2a. physics.
The minimal indivisible amount of a specified physical property (eg momentum or electromagnetic radiation energy, etc) that can exist;
2b. physics.
A unit of this, eg the photon. Often as adj.
Example: quantum effect

adj

1. Major, large or impressive but also sudden, unexpected or abrupt, etc.

Etymology: 17c: from Latin, neuter of quantus how much.