[ˌreɪdɪˈeɪʃn], (Noun)

Definitions:
- the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles which cause ionization

- divergence out from a central point, in particular evolution from an ancestral animal or plant group into a variety of new forms
(e.g: evolution is a process of radiation not progression)


Phrases:

Origin:
late Middle English (denoting the action of sending out rays of light): from Latin radiatio(n-), from radiare ‘emit rays’ (see radiate)