The phrase "tough job" is an idiomatic expression that means a difficult, challenging or demanding task. It implies that the work involved requires strength, endurance and perseverance to complete successfully. The term can be used in various contexts such as describing a physically demanding job like construction work, a mentally exhausting job like managing a large team, or an emotionally challenging job like counseling. In essence, the phrase conveys that the task at hand is not easy and requires great effort to accomplish.