迅 seon³ {xùn}

1. rapid
2. fast

迅速 seon³ cuk¹ {xùn sù}

1. rapid
2. speedy
3. fast

迅雷 seon³ leoi⁴ {xùn léi}

thunderbolt

迅猛 seon³ maang⁵ {xùn měng}

quick and violent

迅疾 seon³ zat⁶ {xùn jí}

1. rapid
2. swift

迅即 seon³ zik¹ {xùn jí}

1. immediately
2. promptly
3. quickly

迅捷 seon³ zit⁶ {xùn jié}

fast and nimble

迅速發展〔--发-〕 seon³ cuk¹ faat³ zin² {xùn sù fā zhǎn}

to develop rapidly

迅速蔓延 seon³ cuk¹ maan⁶ jin⁴ {xùn sù màn yán}

1. rapid spread
2. to spread rapidly

迅雷不及掩耳 seon³ leoi⁴ bat¹ kap⁶ jim² ji⁵ {xùn léi bù jí yǎn ěr}

(a swift clap of thunder leaves no time for one to cover the ears); to be extremely sudden and swift