「西」(nishi) means "west." It's one of the four cardinal directions, directly opposite to "東." You might use it to describe where the sun sets, for instance, "西の空" (nishi no sora), meaning "the western sky."

「西(にし)」は「西(にし)の方向(ほうこう)」という意(い)味(み)です。方(ほう)角(がく)の一個(ひと)つ。例(れい)：「西(にし)の空(そら)。」