noun-modifying (irregular)
Prenominal adjective used to describe something that is amusing, funny, or interesting. Often appears in compounds like 面白い (おもしろい) or 面白半分 (おもしろはんぶん).
彼は面白い話をたくさん知っている。
He knows many amusing stories.
面白半分でそんなことをしてはいけない。
You shouldn't do that just for fun.