unshakable

not easily panicked or upset we need the kind of leader who will be unshakable in a national crisis Synonyms imperturbable, nerveless, unflappableRelated Words calm, collected, composed, cool, coolheaded, icy, nonchalant, placid, self-collected, self-composed, self-possessed, serene, steely, tranquil, undisturbed, unperturbed, unruffled, unshaken, untroubled, unworriedNear Antonyms panicky; aflutter, anxious, dithery, edgy, het up, hung up, jittery, jumpy, nervous, nervy, perturbed, shaky, tense, troubled, uneasy, upset, uptight, worriedAntonyms perturbable, shakable (or shakeable)