unaccountable

/ˌʌn.əˈkaʊn.t̬ə.bəl/

形容词

无须对…作出解释；不必对…负责
an unaccountable and inefficient bureacracy
不负责且效率低下的官僚体系
难以解释的；无法理解的
For some unaccountable reason, he keeps his wallet in his underwear drawer.
不知何故，他把钱包放在内衣抽屉里。