What is the origin of がち in 病気がち?


I know from my dictionary that 病気がち means "proneness to being ill". 病気 just
means illness, so where does the がち come from?

My research so far: I think がち might be the ます-stem of the verb 勝つ. The
dictionary supports this hypothesis as it lists 勝ち as a suffix meaning "apt to
do; tend to do (used to describe a negative tendency)". It also lists 涙勝ち as
an "archaism" for "prone to crying" which further supports my hypothesis.

I have the following questions:

  1. Is 勝つ really the origin of がち in 病気がち?
  2. Why is a very **positive** verb such as 勝つ used to describe "being prone to something" in a **negative** way?
  3. Are there any other examples of 勝つ being used in a negative way?
  4. Are there any similar commonly used words ending in 勝ち?




>   1. Is 勝つ really the origin of がち in 病気がち?
>

Yes I think so. But in modern Japanese this suffix is usually written in
hiragana.

>   2. Why is a very positive verb such as 勝つ used to describe "being prone to
> something" in a negative way?
>

In modern Japanese it mainly means _to win_ , but 勝つ also means _to outweigh_
or _to outperform_. Such ～がち suffix survives mainly in some fixed phrases. I
think ～がち is not necessarily negative, as seen in the examples below.

>   3. Are there any other examples of 勝つ being used in a negative way?
>   4. Are there any similar commonly used words ending in 勝ち?
>

Here are some common phrases that are safely usable in modern Japanese.

  * [～しがち](http://eow.alc.co.jp/search?q=%E3%81%97%E3%81%8C%E3%81%A1%E3%81%A7%E3%81%82%E3%82%8B): (na-adj) _tend to do ～_ (perhaps this is the most common example)
  * ありがち: (na-adj) _common_ , _frequently seen_ (it does not have negative connotations)
  * 荷が勝つ: (idiom) _～ is too much load_ (for someone)
  * 伏し目がち: (na-adj) _with eyes downcast_
  * 赤みがかった(色)/青みがかった(色): _reddish/blueish (color)_

Theoretically, I think がち can be used with any action verbs, and you can find
some examples in [this
list](http://dictionary.goo.ne.jp/jn/42286/example/m0u/%E3%81%8C%E3%81%A1/)
(note that these are from relatively old novels). But がち sounds fairly
literary today if used outside of fixed phrases.




>   1. Is 勝つ really the origin of がち in 病気がち?
>

Yes I think so. But in modern Japanese this suffix is usually written in
hiragana.

>   2. Why is a very positive verb such as 勝つ used to describe "being prone to
> something" in a negative way?
>

In modern Japanese it mainly means _to win_ , but 勝つ also means _to outweigh_
or _to outperform_. Such ～がち suffix survives mainly in some fixed phrases. I
think ～がち is not necessarily negative, as seen in the examples below.

>   3. Are there any other examples of 勝つ being used in a negative way?
>   4. Are there any similar commonly used words ending in 勝ち?
>

Here are some common phrases that are safely usable in modern Japanese.

  * [～しがち](http://eow.alc.co.jp/search?q=%E3%81%97%E3%81%8C%E3%81%A1%E3%81%A7%E3%81%82%E3%82%8B): (na-adj) _tend to do ～_ (perhaps this is the most common example)
  * ありがち: (na-adj) _common_ , _frequently seen_ (it does not have negative connotations)
  * 荷が勝つ: (idiom) _～ is too much load_ (for someone)
  * 伏し目がち: (na-adj) _with eyes downcast_
  * 赤みがかった(色)/青みがかった(色): _reddish/blueish (color)_

Theoretically, I think がち can be used with any action verbs, and you can find
some examples in [this
list](http://dictionary.goo.ne.jp/jn/42286/example/m0u/%E3%81%8C%E3%81%A1/)
(note that these are from relatively old novels). But がち sounds fairly
literary today if used outside of fixed phrases.

