In informal British English, the mockers is bad luck that spoils a plan. You almost always hear it inside one set phrase: put the mockers on (someone or something). The rain put the mockers on the picnic means the rain ruined it, as if it had jinxed the day. People say it with a half-smile — everyday talk, not a formal word, and not really American. It looks like it should mean “people who mock you,” from the verb mock, but that is a different reading. In this sense it is an old slang noun for a jinx, and it barely lives outside that phrase.

（英式口語）破壞計畫、帶來霉運；幾乎只出現在 put the mockers on