Pelagianism n 1: the theological doctrine put forward by Pelagius which denied original sin and affirmed the ability of humans to be righteous; condemned as heresy by the Council of Ephesus in 431
Pelagianism \Pe*la"gi*an*ism\, n. [Cf. F. p['e]lagianisme.] The doctrines of Pelagius. [1913 Webster]