Synonyms and related words :
agile, alert, alive, attentive, awake, bright, calm, coolheaded, inexcitable, keen, nerveless, nimble, on the, on the alert, on the ball, on the job, prompt, qui vive, quick, ready, relaxed, rock-steady, sharp, sleepless, smart, steady, steady-handed, steady-nerved, steel-nerved, strong-nerved, unabashed, unappalled, unawed, unblenching, uncowed, uncringing, undaunted, undismayed, unfaltering, unflinching, unintimidated, unnervous, unnodding, unquivering, unshaken, unshaky, unshrinking, unsleeping, unstrained, untremulous, unwavering, unwinking, wakeful, wide-awake, without a tremor