The adjective indifferent means someone who is not concerned in something.

Synonyms are unfeeling, callous, distant, or nonchalant.

The word origins from Old French (14th century) indifferent meaning “impartial” or directly from Latin indifferentem meaning “not differing, not particular, of no consequence, neither good nor evil”. It comes from in– meaning “not, opposite of” plus differens, present participle of differre meaning “set apart”.

Don’t be a writer if you are indifferent about the sufferings of the current society.

He has an indifferent attitude towards his colleagues.

She tried to act indifferent despite the severe criticisms she received.