当 - Hit the Top So Hard Sparks Fly

Readings & Meanings:

あ（−たる）

あ（−てる）

トウ

to hit, to win, to guess

Common Usage:

弁当

本当

Examples:

このお弁当は本当にうまそう！

宝くじに当たればうれしいなぁ。

Translations:

This bento really looks good!

Wouldn't it be nice to win the lottery...

Bonus:

当たり is the word you say in the board game 囲碁 when you are about to take your opponent's stones. It's like "Check" in English.

(Don't know what I'm talking about? You're obviously not familiar with the great old anime, Hikaru no Go. Wikipedia link. Get acquainted.

References:

http://www.jlptstudy.com/2/index.html and http://www.thejapanesepage.com/kanji/kanji/a.htm