IMBECILITY Meaning of IMBECILITY in English [im.be.cil.i.ty] n, pl -ties (1533) 1: the quality or state of being imbecile or an imbecile 2. a: utter foolishness; also: futility b: something that is foolish or nonsensical Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012