1.
speed; quickness; rapidity
Noun formed from 速い (fast), referring to how fast something moves or happens. Also used for speed as a magnitude in everyday and scientific contexts.
速さを競う。
to compete in speed.
車の速さに驚いた。
I was surprised by the car's speed.
仕事の速さでは、彼女に誰もかなわない。
When it comes to how fast she works, no one can match her.
Formed from the i-adjective 速い + さ (a suffix that turns adjectives into nouns expressing degree). Refers to the rate of motion or how quickly something is done.
COMMON COLLOCATIONS:
- 音の速さ: the speed of sound
- 速さを増す: to increase speed
- 目にも留まらぬ速さ: dizzying speed (lit. too fast for the eye to catch)
SIMILAR WORDS:
- 速度: speed, velocity — more technical and measured (e.g. km/h); 速さ is the everyday word
- 早さ: earliness — same reading but written 早, about timing (being early) rather than rate of motion