[im.be.cile] n [F imbecile, n., fr. adj., weak, weak-minded, fr. L imbecillus] (1802) 1: a mentally deficient person; esp: a feebleminded person having a mental age of three to seven years and requiring supervision in the performance of routine daily tasks of self-care
2: fool, idiot -- imbecile or im.be.cil.ic adj