反 (Kanji for anti) | KANJIDAMAGE

Onyomi

HAN

HAN Solo threw your Mom's crotch off a cliff because he's anti-herpes.

反対(はんたい) する	against it!!!!!!!!!! ★★★★☆ 反 (anti) + 対 (against) = 反対 (against it!!!!!!!!!!) to be against something
反則(はんそく)	foul! To break a rule! ★★☆☆☆ 反 (anti) + 則 (rule) = 反則 (foul! To break a rule!)
反抗(はんこう) する	rebel ★★☆☆☆ 反 (anti) + 抗 (oppose) = 反抗 (rebel) to be rebellious, defiant. To start a revolt. Unlike the related words 抵抗　（ていこう）　and 対抗　（たいこう）、　反抗 has the nuance of 'rebel for the fuck of it,' like a teenager would.
反応(はんのう)	a reaction ★★☆☆☆ FP 反 (anti) + 応 (react) = 反応 (a reaction ) a reaction - despite the 反 kanji, 反応 is not neccesairly a bad reaction. As a noun, it's value-free. (careful! This is pronounced NOU, not OU)

	Meaning	Hint	Radical
反	anti	CLIFF
友	friend	NARUTO

Jason Newsted was seen as the Anti - CLIFF by old-school Metallica fans.
NARUTO is your friend if you're an anime nerd.

Alternate mnemonic: only FRIEND has a "head" poking up above the horizontal line, and friends have heads.