Difference between ほとんど～ない, めったに～ない and まれ


is there a difference in nuance or formality between ほとんど～ない, めったに～ない and まれ?




First lets take on `ほとんど～ない` and `めったに～ない`

The big difference between the two can be expressed with these two keywords:
`程度` and `頻度`.

  * `ほとんど～ない` expresses `程度` (you could think of it as "degree" or "extent") **and** `頻度` (frequency) (credit @sawa for pointing out ほとんど has both)

  * `めったに～ない` expresses `頻度` only (or `回数の多さ`, you could think of it as "frequency" or "how often something happens (or is performed)). Also, `めった` in 漢字 is `滅多`. Notice the relationship with `多`?

Lets look at some examples:

> 漢字がほとんど読めない
>
> 彼の声がほとんど聞こえない

In the above examples, the `ほとんど` cannot be replaced with `めったに`. Do you see
why? The concept of "how often" for the ability to read `漢字` and ability to
hear someones voice doesn't make much sense.

However, lets look at an example were both can be used.

> テレビをほとんど見ない
>
> テレビをめったに見ない

Both can be used here. However, I feel that `ほとんど～ない` is more common (Googling
both phrases gave me a lot more hits for `テレビをほとんど見ない`.) There also may be
other subtle differences, however I could not find conclusive evidence at this
time (if anyone has any insight please let me know!).

Also,

> めったに見ない車

When I read the above (the action of seeing), I think `めったに～ない` is better here
(unfortunately that might be a personal opinion).

Now, lets add `まれ` to the bunch. `まれ` falls under the same category as `めったに`,
in that it expresses frequency. The difference is in the usage (the meaning is
exactly the same as `めったに見ない`).

> まれに見ない // Not Japanese
>
> まれに見る // Okay

`まれ` technically is already a negative expression meaning
`実現・存在することが非常に少ないさま。また、数少なくて珍しいさま`
([reference](http://dictionary.goo.ne.jp/leaf/jn2/210188/m0u/)), so you can't
use it with a negative as in the first example because it would become a
double negative.




First lets take on `ほとんど～ない` and `めったに～ない`

The big difference between the two can be expressed with these two keywords:
`程度` and `頻度`.

  * `ほとんど～ない` expresses `程度` (you could think of it as "degree" or "extent") **and** `頻度` (frequency) (credit @sawa for pointing out ほとんど has both)

  * `めったに～ない` expresses `頻度` only (or `回数の多さ`, you could think of it as "frequency" or "how often something happens (or is performed)). Also, `めった` in 漢字 is `滅多`. Notice the relationship with `多`?

Lets look at some examples:

> 漢字がほとんど読めない
>
> 彼の声がほとんど聞こえない

In the above examples, the `ほとんど` cannot be replaced with `めったに`. Do you see
why? The concept of "how often" for the ability to read `漢字` and ability to
hear someones voice doesn't make much sense.

However, lets look at an example were both can be used.

> テレビをほとんど見ない
>
> テレビをめったに見ない

Both can be used here. However, I feel that `ほとんど～ない` is more common (Googling
both phrases gave me a lot more hits for `テレビをほとんど見ない`.) There also may be
other subtle differences, however I could not find conclusive evidence at this
time (if anyone has any insight please let me know!).

Also,

> めったに見ない車

When I read the above (the action of seeing), I think `めったに～ない` is better here
(unfortunately that might be a personal opinion).

Now, lets add `まれ` to the bunch. `まれ` falls under the same category as `めったに`,
in that it expresses frequency. The difference is in the usage (the meaning is
exactly the same as `めったに見ない`).

> まれに見ない // Not Japanese
>
> まれに見る // Okay

`まれ` technically is already a negative expression meaning
`実現・存在することが非常に少ないさま。また、数少なくて珍しいさま`
([reference](http://dictionary.goo.ne.jp/leaf/jn2/210188/m0u/)), so you can't
use it with a negative as in the first example because it would become a
double negative.

