1 N-SING 内幕;实情;真相 If someone gives you the low-down on a person or thing, they tell you all the important information about them. 内幕;实情;真相 [informal]
SYN information, intelligence, info [informal] , inside story
2 ADJ-GRADED [ADJ n] 卑鄙的;无耻的;下流的 You can use low-down to emphasize how bad, dishonest, or unfair you consider a particular person or their behaviour to be. 卑鄙的;无耻的;下流的 [informal, emphasis]
SYN mean, low, base, cheap [informal]