*one piece ch 1000 spoiler* what does チャキ mean?


I just read this chapter and was wondering what this sfx meant.

for context; luffy is passing big mom & kaido while zoro is observing what he
is doing.

![enter image description here](https://i.stack.imgur.com/8uMIN.jpg)

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

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

