Difference between 代用 and 代わり?

[FlamySerpent]

I just can’t get it. WK says that 代わり is ‘Substitute, replacement’ and 代用 is ‘Substitution’ but I can’t understand the difference in english between those too.

[Abstormal]

The way I understand it the first is a noun; the person or thing doing/being used as replacement.
Second is more the act of, yet not quite verb form as it isn’t “to substitute”. The substitute is being used as a substitution, if that makes sense. The two are used differently in English.
An example sentence;
"MacGyver can use gum as a substitution for anything, usually glue. It’s a good substitute cause it keeps things together. "

A native might explain it better (I’m Norwegian)
But that is how I understand the words =)

[jjatria]

For this sort of thing I find it useful to look at Japanese dictionaries. My paper dictionary for elementary school children (the one from NHK Easy News) says:

「代わり」

1. ある人がする役目を、ほかの人がすること。またはその人。
2. つぐない。うめ合わせ。

「代用」
ほかのものの代わりにつかうこと。

So other than the additional meaning for 「代わり」 (which I was entirely unaware of), it seems as if they are pretty close. The first definition makes it seem as if 「代わり」 is mostly about people: either the person doing the substitution (the “substitute”, or “replacement”) or the substitution itself. The second definition makes it seem as if 「代用」 is less about the person doing the replacement (if there is a person), and more about the replacement itself.

Maybe this is what @Abstormal meant (but they are both definitely nouns).

[Protonstorm]

I’m not sure how much Japanese grammar you know, so forgive me if I over-explain things. Basically, the difference lies in the origin of the words and thus the nuance in how they are perceived. 代わり comes from the verb 代わる, or “to be substituted”. This verb is of early Japanese origin. 代用 can also be made into a verb by adding する to make 代用する. 代用 is a word of Chinese origin and thus uses the on’yomi for both the kanji. While the translation into English is “substitute” for both, it’s important to note that 代用 feels more academic and formal (maybe to help you visualize this imagine that this is the “utilization of substitution” or something more literal along those lines). Thus, you would be more likely to use it in a more literary or formal setting. 代わり, on the other hand, feels less formal and is more likely to be used in casual language.

[FlamySerpent]

Ohhh okay! Thanks for the answers!

[chrispthompson]

I put this question on HiNative just now and got a response from a native speaker – they are the same, but 代わり has a more colloquial feeling.