- 1[usually before noun] happening in a short period of time rapid change/expansion/growth a rapid rise/decline in sales The patient made a rapid recovery.
- 2done or happening very quickly a rapid pulse/heartbeat The guard fired four shots in rapid succession. The disease is spreading at a rapid rate. Which Word?fast / quick / rapidThese adjectives are frequently used with the following nouns:
fast ~ quick ~ rapid ~ car glance change train look growth runner reply increase pace decision decline lane way progress - Fast is used especially to describe a person or thing that moves or is able to move at great speed.
- Quick is more often used to describe something that is done in a short time or without delay.
- Rapid, swift, and speedy are more formal words.
- Rapid is most commonly used to describe the speed at which something changes. It is not used to describe the speed at which something moves or is done:a rapid train We had a rapid coffee.
- Swift usually describes something that happens or is done quickly and immediately:a swift decision The government took swift action.
- Speedy has a similar meaning:a speedy recovery. It is used less often to talk about the speed at which something moves:a speedy car
- For the use of fast and quick as adverbs, see the usage note at quick.
NAmE//rəˈpɪdət̮i//
noun [uncountable] the rapidity of economic growth The disease is spreading with alarming rapidity. NAmE//ˈræpədli//
adverb a rapidly growing economy Crime figures are rising rapidly.See rapid in the Oxford Advanced Learner's DictionaryCheck pronunciation: rapid