Literally means "huh?" in Japanese. Popularized by Kenshin in "Rurouni Kenshin" when he uses it in funny situations.

A term Kenshin uses when confused or minorly hurt

When your really confused or hit and act like kenshin himura.

A Japanese expression of confusion. Often used by otaku to indicate confusion/disorientation. People who read/watch "Rurouni Kenshin" may pick up the habit of saying "Oro!" because Himura Kenshin says it often in the manga/anime.

A word used when suprised or confused.

it's a word used by the main protagonist, Kenshin, in the anime, Ruruoni Kenshin as an expression. it doesnt really mean anything in particular but it does get it's meaning from the manner in which the character says it.

It's what Kenshin Himura says in Rurouni Kenshin whenever he gets hit in the head with something. Like a teacup or a brick or something of the sort.