Synonyms of swiftly in English:

swiftly


See US English definition of swiftly

See UK English definition of swiftly

adverb

1‘he went swiftly through the house’

SYNONYMS
rapidly, quickly, fast, speedily, briskly, at high speed, at full tilt, like the wind, like lightning, at breakneck speed, as fast as one's legs can carry one, as swift as an arrow
informal double quick, nippily, like the clappers
literary apace
ANTONYMS

slowly

2‘the police reacted swiftly’

SYNONYMS
promptly, immediately, instantly, instantaneously, without delay, post-haste, in a flash, in a trice, in the wink of an eye, in an instant, in no time, in no time at all
readily, punctually, meteorically
suddenly, abruptly, unhesitatingly, hastily, hurriedly, precipitately, headlong
informal before you can say Jack Robinson, before you can say knife, like a shot, like greased lightning, at warp speed, p.d.q., pretty damn quick, lickety-split, in a jiff, in a jiffy, pronto, in less than no time
ANTONYMS

unhurriedly, in due course