「左」(hidari) means "left" or "left side". It's used to indicate direction or position, just like "右" but for the opposite side. For instance, "左手" (hidari-te) refers to your "left hand" or "左に座る" (hidari ni suwaru) means "to sit on the left."

「左」(ひだり)は「左側」(ひだりがわ)という意味(いみ)です。方向(ほうこう)や位置(いち)を示(しめ)します。例(れい)：「左」(ひだり)に座(すわ)る。」