name for certain heretics, late 14c., also Loller, from Middle Dutch lollaerd, a word applied pejoratively to members of semi-monastic reforming sects active in the Low Countries from c. 1300 who devoted themselves to the care of the sick and poor. The Dutch word means literally "mumbler, mutterer, one who mutters prayers and hymns," from lollen "to mumble or doze."
They were so called by critics who saw in them heretics pretending to humble piety, from lollen "to mumble or doze." In transferred use it became the generic late Middle English term for groups suspected of heresy, especially followers of John Wyclif. Related: Lollardism (the modern word); Lollardy (the old one).