1: not made use of, won, or claimed 2 a: no longer possessed b: no longer known 3: ruined or destroyed physically or morally :desperate 4 a: taken away or beyond reach or attainment :denied<regions lost to the faith>b:insensible, hardened<lost to shame> 5 a: unable to find the way b: no longer visible c: lacking assurance or self-confidence :helpless 6:rapt, absorbed<lost in reverie> 7: not appreciated or understood :wasted<their jokes were lost on me> 8: obscured or overlooked during a process or activity <lost in translation> 9: hopelessly unattainable :futile<a lost cause>