n. The act of flowing or issuing from a fountainhead or origin; emission; radiation.n. In philosophy: Efficient causation due to the essence and not to any particular action of the cause. Thus, when the trunk of a tree is moved, the branches go along with it by virtue of emanation. Hence — The production of anything by such a process of causation, as from the divine essence.n. That which issues, flows, or is given out from any substance or body; effiux; effiuvium: as, the odor of a flower is an emanation of its particles.n. In algebra, the process of obtaining the successive emanants of a quantic.n. Specifically, in radioactivity, an unstable gaseous disintegration-product spontaneously produced from a radioactive substance.