absence or suppression of passion, emotion, or excitement.

lack of interest in or concern for things that others find moving or exciting.

Also, apatheia, apathia

noun

care , concern , feeling , interest , passion , sensitivity , sympathy , warmth

noun

aloofness , coldness , coolness , detachment , disinterest , dispassion , disregard , dullness , emotionlessness , halfheartedness , heedlessness , indifference , insensibility , insensitivity , insouciance , lassitude , lethargy , listlessness , passiveness , passivity , stoicism , unconcern , unresponsiveness , impassivity , incuriosity , incuriousness , insensibleness , phlegm , stolidity , stolidness , uninterest , acedia , doldrums , hebetude , immobility , impassiveness , inaction , inappetency , inertia , inertness , languor , minauderie , nonchalance , torpor