Unlike most marine mammals (such as seals or whales), sea otters do not have a layer of insulating blubber. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths.
Defined, an axiomatic system is a set of axioms used to derive theorems. What this means is that for every theorem in math, there exists an axiomatic system that contains all the axioms needed to prove that theorem. An axiom is a statement that is considered true and does not require a proof. It is considered the starting point of reasoning. Axioms are used to prove other statements.
The term has subtle differences in definition when used in the context of different fields of study. As defined in classic philosophy, an axiom is a statement that is so evident or well-established, that it is accepted without controversy or question. As used in modern logic, an axiom is simply a premise or starting point for reasoning.