Dig \Dig\, v. i. 1. To work hard or drudge; specif. (U. S.): To study ploddingly and laboriously. [Colloq.] Peter dug at his books all the harder. --Paul L. Ford. 2. (Mach.) Of a tool: To cut deeply into the work because ill set, held at a wrong angle, or the like, as when a lathe tool is set too low and so sprung into the work. {To dig out}, to depart; to leave, esp. hastily; decamp. [Slang, U. S.]