”、“得不偿失”、“划不来”的意思。

ajacobsladderisaladdermadeofropeorcable,usuallywithwoodenrungs.itisdroppedoverthesideofashiptoenablepeopletoascendfromordescendtosmallboatsalongside.harborpilotsusuallycomeaboardviaajacobsladder.

thejacobsladdergetsitsnamefromanincidentinthebookofgenesis（28：12）.thepatriarchjacobfallsasleepandtheavision：“andhedreamed,andbeholdaladdersetupontheearth,andhetopofitreachedtoheaven；andbeholdtheangelsofgodascendinganddescendingonit.”

jacobsladderhasbeenusedinatleasttwootherquiteearthlymeanings.asmallplantwithaflower-and-leafformationresemblingaladderbearsthisname.inengland,alsowhatweamericanscall“runs”inhosierywereformerlycalledjacobsladders.nowadaystheyaresimplyladders.

jacobsladder可以登天，所以美国黑社会的thieveslatin（盗贼的