What is the meaning of the suffix 之助?


I know that 之助 is a suffix for generating names. But what is its intended
meaning?

Also, there's a lexical item 承知の助 which [I understand is meant to be an
interjection "Understood!"](http://dictionary.goo.ne.jp/leaf/jn2/109348/m0u/).
What's going on there? Is this usage meant to be humorous?




Yes, [之助]{の・すけ} is appended to [承知]{しょう・ち} in order to make the word sound
humorous, regardless of whether it actually sounds funny or not. It's a kind
of play on words.

During the Edo period ([江戸]{え・ど}[時代]{じ・だい} 1603 - 1868), many words were
modified for fun. Turning a plain word into a name-style word without changing
the meaning (or with growing the meaning sometimes) was one of popular ways to
be humorous. 承知之助 is an example of it. Another example of this kind of 〜之助 is

> いい[気味]{き・み}[之助]{の・すけ}

いい気味 of Edo vocabulary means "feeling good" or "happy to know the unhappiness
of whom one dislikes." 之助 was a common last part of men's names, such as
[吉]{きち}之助, [半]{はん}之助, etc., in the Edo period. The name-like compound word
いい気味之助 means the same as いい気味 but the nuance is somewhat humorous.

[承知]{しょう・ち}[之助]{の・すけ} is also a name-like compound word, and means the same as
承知 but the nuance is somewhat humorous by using 之助. This 之助 is playfully added
to 承知, just for fun.

Sometimes, animals were used to create humorous words as well. For example,
[面白]{おも・しろ}い was turned into [面白]{おも・しろ}[狐]{ぎつね} or 面白[狸]{だぬき}. A derivative
of 面白狸 was
[面白狸の腹鼓](http://dictionary.goo.ne.jp/leaf/jn2/33405/m0u/%E9%9D%A2%E7%99%BD%E7%8B%B8%E3%81%AE%E8%85%B9%E9%BC%93/).
All of them meant 面白い, although in some cases they seemed to imply additional
meanings for extra fun.

Kami ([神]{かみ}) was also used to create humorous words in order to emphasize
the meaning. For example, [上]{あ}がったり was turned into 上がったり[大明神]{だいみょうじん} in
some conversation during the Edo period. 上がったり大明神 was a word which humorously
emphasized the meaning of [上がったり](http://gogen-allguide.com/a/agattari.html).

However, most those name-style words couldn't have survived. We can see those
old humorous words in [草双紙](https://en.wikipedia.org/wiki/Kusaz%C5%8Dshi) or
Edo language dictionaries, such as
[江戸語の辞典](http://www.amazon.co.jp/%E6%B1%9F%E6%88%B8%E8%AA%9E%E3%81%AE%E8%BE%9E%E5%85%B8-%E8%AC%9B%E8%AB%87%E7%A4%BE%E5%AD%A6%E8%A1%93%E6%96%87%E5%BA%AB-422-%E5%89%8D%E7%94%B0-%E5%8B%87/dp/4061584227/),
but almost never hear those words (いい気味之助, 面白狐, 面白狸, 上がったり大明神 etc.) used in
present-day life. I guess that the extinction of them is due to changes of
people's sense of humor and of naming conventions.

But somehow, 承知之助 has survived. Most of today's people don't use it because it
sounds unfunny and too old, but at least we know the meaning and the usage of
承知之助.

### 付け足し言葉

Nowadays, these extra words, such as 〜之助, 〜狸の腹鼓, 〜大明神 etc., are called
[付]{つ}け[足]{た}し[言葉]{こと・ば}.

付け足し言葉s are not only name-style words but also any kind of additional words
humorously following the base word. People enjoy the rhythm of phrase,
association of the meanings of words, and something like that. For example,
these are 付け足し言葉.

> 「[驚]{おどろ}き [桃]{もも}の[木]{き} [山椒]{さんしょ}の[木]{き}」(means 驚き with humorous nuance)
>
> 「お[茶]{ちゃ}の[子]{こ}さいさい[河童]{かっぱ}の[屁]{へ}」 (means
> [お茶の子](http://dictionary.goo.ne.jp/leaf/jn2/31600/m0u/)(easy) with humorous
> nuance)
>
> 「しーらんぺったんゴリラ」(means [知]{し}らない with humorous nuance)

In many cases, 付け足し言葉 is young children's fun these days. A picture book
『[おっと合点承知之助](http://www.ehonnavi.net/ehon/4136/%E3%81%8A%E3%81%A3%E3%81%A8%E5%90%88%E7%82%B9%E6%89%BF%E7%9F%A5%E4%B9%8B%E5%8A%A9/)』
is popular in Japan.

Of course, there are some adults enjoying 付け足し言葉 as well, though. But it's
like a hobby or a study.

So, the 之助 in 承知の助 implies something more than the literal meaning, because
it's 付け足し言葉.

