unflappable Synonyms

imperturbable as cool as a cucumber unagitated undisturbed unshaken unshakable unruffled unmoved tranquil together stolid stoical stoic steady sober laid-back easygoing unperturbed unflustered unemotional unbothered self-controlled untroubled unfazed unexcitable even-tempered coolheaded unshockable levelheaded level-headed serene self-possessed self-confident easy dispassionate disimpassioned detached cool-headed cool controlled confident composed collected chilled centered calm equable equanimous impassive self-assured