As a noun unconcern
is (nonstandard|obsolete) indifference or lack of concern.
As an adjective apathetic is
void of feeling; not susceptible of deep emotion; passionless; indifferent.
unconcern
English
Noun
(
en noun)
(nonstandard, obsolete) indifference or lack of concern.
Related terms
* unconcerned
apathetic
English
Alternative forms
* apathetical
Adjective
(
en adjective)
Void of feeling; not susceptible of deep emotion; passionless; indifferent.
Of, or pertaining to apatheism.
Synonyms
* indifferent. impassive
Related terms
* apatheism
* apatheist