axiom
//ˈæk.si.əm//
Noun
axiomSingular
axiomsPlural
1
A statement or proposition that is regarded as being established, accepted, or self-evidently true, serving as a starting point for further reasoning or argument.
It is an axiom of science that every effect has a cause.
2
A fundamental principle or rule that is universally accepted within a particular field or system of thought.
One axiom of economics is that resources are limited.