Ma'anar ƙamus na kalmar "Babban Mataimakin Shugaban kasa" yana nufin babban jami'in gudanarwa ko jami'in kamfani wanda ke rike da babban matsayi a cikin kamfani ko kungiya, yawanci yana ba da rahoto kai tsaye ga Shugaban kasa ko Shugaba. Babban Mataimakin Shugaban kasa yana da alhakin kulawa da sarrafa sassa daban-daban da ayyuka a cikin kamfani, kuma galibi yana shiga cikin yanke shawara mai mahimmanci, tsarin kasuwanci, da sarrafa kuɗi. Matsayin Babban Mataimakin Shugaban Kasa ana ɗaukarsa ɗaya daga cikin manyan matakan jagoranci a kamfani ko ƙungiya.