low-down
/ˈləudaun; `lo`daʊn/ adj[attrib 作定语]
(infml 口) dishonourable; underhand 卑鄙的; 不名誉的; 偷偷摸摸的
That was a pretty low-down trick to play! 玩弄那套伎俩真可耻! low-down, n (idm 习语) give sb/get the low-down (on sb/sth) (infml 口) tell sb/be told the true facts (about sb/sth) 告诉某人[获悉]（有关某人[某事物]的）真相
Give me the low-down on her divorce. 把她离婚的实情告诉我吧.