Meaning of シャキン or シャッキン used to support someone


In a manga, before the start of a boxing match, one of the boxers looks at his
friends in the audience and says:

> シャキ〜ン

Then they reply more or less in the same way:

> しゃっきい〜ん

What is the meaning of this expression? Is it an onomatopoeic word used to
support someone? Since the match has a special prize of one million yen for
the winner, could it be 謝金? [Here you can see the
page](https://i.stack.imgur.com/2MljF.jpg) where it is taken from. Thank you
for your help!




It is an onomatopoeia originally mimics the sound some metallic material makes
when it swiftly extends, like the way the joint makes when a folding knife
springs out. But it is also used to express (comically) that someone feels at
100% condition or full of spirit.

It's often uttered with striking certain poses. See
[here](https://dic.pixiv.net/a/%E3%82%B7%E3%83%A3%E3%82%AD%E3%83%BC%E3%83%B3).

[![enter image description
here](https://i.stack.imgur.com/y2PA5.jpg)](https://i.stack.imgur.com/y2PA5.jpg)




「シャキ～ン」 is an onomatopoeia expressing one's feeling when bracing oneself up
just before or at the start of an important event. Round 1 is just starting
here so, that is how he feels.

「しゃっきい〜ん」 said by that girl would be a pun-like joke. 「借金{しゃっきん}」 means
"debt(s)".

I do not see how 「謝金{しゃきん}」 ("renumeration") would be uttered here. It is a
much bigger (and less often used) word than 「借金」.

