THESAURUS
Forgetfulness
abandon, careless abandon, carelessness, casualness, cursoriness, disregardfulness, easiness, hastiness, heedlessness, inconsiderateness, inconsideration, indifference, insouciance, lack of foresight, laziness, lethe, oblivion, obliviousness, offhandedness, perfunctoriness, recklessness, regardlessness, sprezzatura, tactlessness, thoughtlessness, unaccommodatingness, unheedfulness, unhelpfulness, unmindfulness, unobligingness, unpreparedness, unreadiness, unsolicitousness, unsolicitude, unthinkingness, unthoughtfulness
ROGET THESAURUS
Forgetfulness
Oblivion
N
oblivion, obliviousness, lethe, forgetfulness, amnesia, obliteration of &c, insensibility to the past, short memory, treacherous memory, poor memory, loose memory, slippery memory, failing memory, decay of memory, failure of memory, lapse of memory, waters of Lethe, waters of oblivion, amnesty, general pardon, repressed memory, forgotten, unremembered, past recollection, bygone, out of mind, buried in oblivion, sunk in oblivion, clean forgotten, gone out of one's head, gone out of one's recollection, forgetful, oblivious, mindless, Lethean, insensible to the past, heedless, non mi ricordo, the memory failing, the memory deserting one, being at fault, being in fault, To the Future.