Questions about example sentences with, and the definition and usage of "Scaredy"

A: That helps!

These characters are talking about things they’re afraid of, and “scaredy stuff” is referring to the category of things people are commonly afraid of. Dipper is saying that in between the three characters, they’re all afraid of all the things that we would normally expect people to be afraid of (be that spiders, ghosts, clowns, snakes, bugs, etc.)

A: A person who gets scared easily or a lot.
I tried translating it in Chinese 胆小鬼.

A: It basically means "scared" so "the scared cat".

A: yes!

A: @masae actually BasmaShebl's answer is not correct.

masae's sentence literally translates to "he [topic] bibiri", which is used in Japanese when someone gets scared (I think). Masae's original translation of his sentence "He is a scaredy cat", therefore is correct! It's actually an English figure of speech meaning "He gets scared easily".