don't-care
/ˈdəʊntˌkɛː/adjective
That shows that one does not care; careless, reckless, unconcerned.
noun
A person who does not care; a careless, unconcerned, or indifferent person.
Origin
Mid 19th century; earliest use found in Catherine Sedgwick (1789–1867). From (I) don't care: see care.