ultrarapid
adjective
ul·tra·rap·id ˌəl-trə-ˈra-pəd 
: marked by an extremely fast rate of motion, activity, succession, or occurrence : extremely or extraordinarily rapid
ultrarapid heating/cooling
a battery that supports ultrarapid charging
Word History
First Known Use
1921, in the meaning defined above
ultrarapid
adjective
as in ultrafast
Synonyms & Similar Words
Relevance
- ultrafast
- rush
- rapid
- vigorous
- strenuous
- accelerated
- high-speed
- energetic
- breathtaking
- swift
- quickened
- expeditious
- hastened
- strong
- hurried
- speedy
- rushed
- breakneck
- hasty
- prompt
- lightning
- ready
- whirlwind
- fast
- quick
- splitting
- blistering
- rattling
- fleet
- galloping
- rapid-fire
- breathless
- brisk
- flying
- dizzy
- zippy
- hot
- snappy
- fleet-footed
- nippy
Antonyms & Near Antonyms
- slow
- sluggish
- unhurried
- languid
- deliberate
- crawling
- dragging
- plodding
- late
- poky
- pokey
- leisurely
- lingering
- laggard
- slowish
- measured
- dilatory
- dallying
- tardy
- dawdling
- poking
- dillydallying
- ultraslow