The differences between 速さ, 早さ,　and 速度


I was emailing a friend and used the phrase "タイピングすることの早さ" which I discovered
was very incorrect. I did some searching on Google and here is what I
discovered:

  * タイピングの速度 <-rare
  * タイピング速度 <-common
  * タイピング速さ <-not found
  * タイピングの速さ <-common

I'm curious as to what the differences between 速さ, 早さ, and 速度 are. Also, why
is の used more commonly with 速さ and not 速度?




The nouns 早さ and 速さ are derived from the adjectival verbs 早い and 速い, which
both can mean both "fast" and "early". Being derived from adjectival verbs,
they are native Japanese words.

On the other hand, 速度 is a Chinese-derived word, which means "speed" or "rate"
(and doesn't mean "earliness").

The kanji 早 is usually used for the sense of "early" and 速 usually for speed,
although these concepts overlap a little. (E.g. 早いですね doesn't need to be "you
are early", it could be "wow, you were fast" in the sense of "you got here
earlier than I expected".)

For the question about typing speed, you can interpret タイピング to have the
status of a Chinese-derived word in the following sense:

Chinese-derived nouns (which are usually two-characters long) can form
compound nouns simply by concatenation (without a joining particle like の).
E.g. 自宅教育 "home-schooling" from 自宅 "home" and 教育 "education".

On the other hand, Japanese-derived nouns are usually connected to other nouns
with の.

Thus we get

> ○ タイピング速度  
>  × タイピングの速度  
>  × タイピング速さ  
>  ○ タイピングの速さ

which concurs with your findings on Google. (Although you shouldn't trust
Google counts!)

Here ○ and × indicate what sounds most natural in the sense of the above
explanation. Of course, you can always combine two nouns with の, so タイピングの速度
is grammatically correct as well.




The nouns 早さ and 速さ are derived from the adjectival verbs 早い and 速い, which
both can mean both "fast" and "early". Being derived from adjectival verbs,
they are native Japanese words.

On the other hand, 速度 is a Chinese-derived word, which means "speed" or "rate"
(and doesn't mean "earliness").

The kanji 早 is usually used for the sense of "early" and 速 usually for speed,
although these concepts overlap a little. (E.g. 早いですね doesn't need to be "you
are early", it could be "wow, you were fast" in the sense of "you got here
earlier than I expected".)

For the question about typing speed, you can interpret タイピング to have the
status of a Chinese-derived word in the following sense:

Chinese-derived nouns (which are usually two-characters long) can form
compound nouns simply by concatenation (without a joining particle like の).
E.g. 自宅教育 "home-schooling" from 自宅 "home" and 教育 "education".

On the other hand, Japanese-derived nouns are usually connected to other nouns
with の.

Thus we get

> ○ タイピング速度  
>  × タイピングの速度  
>  × タイピング速さ  
>  ○ タイピングの速さ

which concurs with your findings on Google. (Although you shouldn't trust
Google counts!)

Here ○ and × indicate what sounds most natural in the sense of the above
explanation. Of course, you can always combine two nouns with の, so タイピングの速度
is grammatically correct as well.

