look up any word, like wcw:
 
1.
White people who emulate Japanese culture. Will usually watch loads of anime, read manga, try and learn the language, and basically love all things Japanese.

Not a derogetory term.
"Why is that girl wearing Harujuko when she's white?" "Oh, she's a total Jap-Chap."
by bankainyu May 16, 2010
 
2.
Referring to a Japanese Man, meaning a small penis.
Steve: "My girlfriend hates the sex we have"

John: "What do you expect? How are you supposed to pleasure her with your Jap Chap"
by Scott247j September 25, 2010