51952
I found an interesting word in a box kind of stamina drugs which said 力強い
(chikaradzuyoi) which means powerful. The interesting thing for me is, I
noticed the word may be interchangeable, like with 強力 (kyouryoku) which means
powerful too, and I mostly use 「強力」rather than「力強い」. Is this a colloquial
matter? Or nuance?
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2017-08-02T00:41:03.977
51944
2017-08-04T15:46:32.773
2017-08-03T03:28:21.863
11104
19128
question
word-choice nuances
Different between 力強い with 強力
According to this answer on
[hinative](https://hinative.com/ja/questions/1271971),「強力な」 focus on the fact
that the vigor or power of something is strong. On the other hand, 「力強い」 bears
the meaning of something that is robust/strong (丈夫な) and you can rely on.

> 「強力な」は、勢いや力が強いことです。 それに対して「力強い」は、頼れる、丈夫な、という意味です。

So in the context of a drug it seems 力強い as you found would make sense as it
could be interpreted like "strong and reliable".

However notice that for example if you look on
[weblio](http://ejje.weblio.jp/content/%E5%BC%B7%E5%8A%9B%E3%81%AA) you find
強力 in 強力な薬 to describe a "powerful drug", so this seems to be the most common
between the two in this case. So either it is strangely used on your drug or
it's maybe done on purpose to catch the buyer's attention.
CC BY-SA 3.0
2017-08-02T02:36:38.607
51949
2017-08-04T15:46:32.773
2017-08-04T15:46:32.773
9831
14205
51944
answer
> stamina drugs which said 力強い (chikaradzuyoi) which mean powerful.  
>  I notice the word in interchangeable way, like 強力 (kyouryoku) which mean
> powerful too, and I mostly use 「強力」rather than「力強い」. Are this colloquial
> matters? or nuance?

It's normally 強力 that we use for the strength of a drug.  
力強い for 強壮剤{きょうそうざい} is an unusual expression, and so it's almost funny but
ambiguous. It's successful for getting the customers' attention.

力強い is more explanatory to me, it's to describe a **_manner_** of something or
someone or a scene.

> デジタル大辞泉 says **きょうりょく【強力】** is
> 力や作用{さよう}が強いこと。また、そのさま。ごうりき：「強力な味方{みかた}」「運動{うんどう}を強力に推進{すいしん}する」

You can say 力強い味方, and maybe also 運動を力強く推進する. We say a work of art is 力強い, but
強力 doesn't work for it.

> **ちからづよい【力強い】**  
>  **１** いかにも力がありそうに見えるさま。力がこもっていて頼もしく感じられるさま。「―・い横綱の土俵入り」「―・い演説」  
>  **２** たよりになるさま。安心できるさま。気強い。「彼に来てもらえば―・い」  
>  （デジタル大辞泉）
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2017-08-02T04:00:25.883
51952
2017-08-02T04:00:25.883
22422
51944
answer
It depends on the context and the collocations.

筆跡が強力だ。 (weird) (bad collocation)  
筆跡が力強い。 (OK) (good collocation)

彼のサポートが力強い。 (OK) (His support is helpful/appreciated/trustworthy.)

彼のサポートは強力だ。 (OK) (His support is strong/powerful.)

彼が側にいてくれると力強い。 (OK)

彼が側にいてくれると強力だ。 (weird) (bad collocation, or grammatically wrong)

この薬の薬効は強力だ。 (OK)

この薬の薬効は力強い。 (This drug's effect is helpful for me.)

この薬は強力だ。 (OK)(This medicine has a strong effect.)

この薬は力強い。(OK, maybe) (I rely on this drug. It's reliable.)
CC BY-SA 3.0
2017-08-02T21:16:31.117
51971
2017-08-03T23:42:13.773
2017-08-03T23:42:13.773
51944
answer
It seems to me that a better translation of 強力 is "with intense force" and
力強い, "sturdy". 強力 describes how it is good in affecting external objects; 力強い
on the other hand how it is good in being unaffected by external fluctuation.

They may be able to be used in place of the other, but not generally
interchangeable, as we rarely say 強力な演技 and 強力な文体, neither 力強い武器 and 力強い刺激.
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2017-08-04T14:57:57.667
52012
2017-08-04T14:57:57.667
7810
51944
answer