Nuclearity refers to the state of being nuclear or having a nucleus. However, there are several synonyms which can be used to describe this concept. Some of these synonyms include "centrality", "coreness", "fundamentality", "essence", and "kernel". Each of these words describes an essential, central, or core aspect of something, just as the nucleus is the central and essential part of an atom. Other synonyms for nuclearity include "pith", "heart", and "center". These words all emphasize the importance and centrality of something, much like the nucleus is the essential component of the atom.