0 always staying calm and controlled, even in difficult situations that would cause other people to worry
1 staying calm and controlled despite problems or difficulties:
He was imperturbable in a crisis.
Rather than change dramatically from administration to administration, government policy will remain moderate and imperturbable.
A citizen of the world, he does not carry foreignness with him, he carries imperturbable aspects of his culture, he practises a literature of resistance.
He knows the members, too, for he has listened with imperturbable courtesy, for over fifty years to all our speeches, good, bad and indifferent.
It recalls with emotion the tranquil courage and the imperturbable faith in the destinies of the free world with which he shared in the trials of the war.
Next, the eight neutrals: patient, wily, constructive, imperturbable, holding the ring by simply refusing to go away and call it a day, which prevents the giants doing so.
He had an easy grace combined with imperturbable solemnity, a combination which amused people; his humour was never broad, but always measured and restrained.
Lane's surgical skill, widely renowned, exhibited imperturbable calm at difficulties encountered during operations.
He was the personification of intrepid gallantry and imperturbable courage.
