IPA: /nɒn.kənˈsɜːrn/
KK: /nɑnˈkənˌsɜrn/
Something that is not a source of worry or anxiety.
Her nonconcern about the exam surprised her friends.
Nonconcern → It is formed from "non-" (meaning not) and "concern" (from Latin "concernere", meaning to sift together or to relate). The word "nonconcern" means something that is not related or does not involve concern.
Think of 'not' ('non-') being added to 'relate' ('concern') — that's why nonconcern means something that does not relate to your worries.