imperturbable
im-per-TUR-buh-buladjMeaning so calm that nothing can upset you
Memory hook IM-PERTURB-able: nothing DISTURBS him. The wind howls, an umbrella flies past and hats blow away, but Grandpa calmly turns the page of his newspaper. He is imperturbable.
Grandpa is imperturbable; he reads his paper calmly even in a thunderstorm.
In context Reporters tried for an hour to rattle the imperturbable scientist, but she answered every rude question in the same quiet, even voice.
Similar unshakable, unruffled, untroubled, unexcitable
Opposite excitable, nervous, touchy
From Latin imperturbabilis: in- (not) + perturbare (to throw into confusion), from turba (turmoil).