turn

This Kanji is pronounced as "ban"
By itself, it means the following:
(1) watch; guard; lookout;
(2) bout, match (sumo);
(3) (one's) turn.

Some common forms of the word when used:

-ban-
番号 （bangou): number, series of digits
eg. .電話番号(denwa bangou) - telephone number
登録番号 (touroku bangou) - registration number
一番 (ichiban): best; first; number one
交番 (kouban): police box; police post
番組 (bangumi): programme
eg. テレビ番組 (terebi bangumi) TV programme
十八番 (juuhachi ban/ohako): number 18; one's favorite stunt/hobby