#1 jack v. [jack up] lift with a special device; "jack up the car so you can change the tire". wn
#2 jack n. [doodly-squat, diddly-squat, diddlysquat, diddly-shit, diddlyshit, diddly, diddley, squat, shit] a small worthless amount; "you don't know jack". wn
#3 jack v. [jacklight] hunt with a jacklight. wn
#4 jack n. [mariner, seaman, tar, Jack-tar, Jack, old salt, seafarer, gob, sea dog] a man who serves as a sailor. wn
#5 jack n. [laborer, manual laborer, labourer] someone who works with their hands; someone engaged in manual labor. wn
vizzz