leap in the darkRISKsomething you do without knowing what will happen as a result 冒险举动，轻举妄动；瞎闯leap in the dark• Critics also worry that compassionate conservatism is a leap in the dark without any empirical evidence to back it up.• The man who hopes to be Chancellor next week can not surely be preparing a leap in the dark.• Ten minutes later - another leap in the dark - he offered the appointment to Churchill.
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