Japanese Pop/J-pop
ジェイポップ
N.
Japanese pop music, a trend in Japan. According to Anime News Network, one of the DJs at J-WAVE, 81.3 FM in Tokyo, originally coined the term, and it quickly became popular among music fans. Some of the most popular J-pop artists include Amuro Namie-san, Hamasaki Ayumi-san, Chemistry, Hirai Ken-san, BoA (one of the few J-pop artists who isn't Japanese) and of course Hayashibara Megumi-san.
Japanese Rock/J-rock
ジェイロック
N.
A term used by people outside of Japan, it's Japanese rock music. Popular J-rock artists include L'Arc~en~Ciel, Glay, Pierrot, X Japan and Malice Mizer.
Jibun (jee-boo-n)
自分
じぶん
Pn.
Self. When used as "I", it is not informal, though there are more formal words of "I". The same goes for "you". Wataru of "Tokimemo" uses "jibun".
Joshikousei (joh-shee-koh-oo-seh-ee)
女子高生
じょしこうせい
N.
An established girl, or more commonly said, a female high school student. You see them wearing a seifuku in Japan. "Kimagure Orange Road" is easily a joshikousei series.
Jump
ジャンプ
V.
Besides the obvious, jumping differs from game to game. In many fighting games, you have your small jump, normal jump and a super jump to avoid an attack or to perform an air attack. Some characters also have a triangle jump in which the character bounces off a wall and goes forward and if you don't know why it's called a triangle jump, the points are the starting point, the bouncing point and the high point of the bounce off the wall. In rpgs, a jump refers to being able to reach a higher platform and it can also refer to a high damage attack (usually) from the air. In platform games, you jump to stomp on an enemy if you're able to, reach a certain point and to avoid gaps that make you lose a life.
Last update - 2006/11/12