[ˈnjuːklɪəs], (Noun)

Definitions:
- the central and most important part of an object, movement, or group, forming the basis for its activity and growth
(e.g: the nucleus of a British film-producing industry)

- the positively charged central core of an atom, consisting of protons and neutrons and containing nearly all its mass


Phrases:

Origin:
mid 17th century (denoting the solid part of a comet's head): from Latin, literally ‘kernel, inner part’, diminutive of nux, nuc- ‘nut’