The Collaborative International Dictionary of English v.0.48:

Lollard \Lol"lard\, n. [LL. Lollardi, Lullardi, from Walter
   Lolhardus, a German; cf. LG. & D. lollen to mumble, to hum,
   sing in a murmuring strain; hence, OD. lollaerd a mumbler, i.
   e., of prayers or psalms, which was prob. the origin of the
   name. See Loll, Lull.] (Eccl. Hist.)
   (a) One of a sect of early reformers in Germany.
   (b) One of the followers of Wyclif in England. [Called also
       Loller.]
       [1913 Webster]

             By Lollards all know the Wyclifities are meant, so
             called from Walter Lollardus, one of their teachers
             in Germany.                          --Fuller.
       [1913 Webster] Lollardism