-birru-

n. [ LL., fr. L. birrus a kind of cloak. See Berretta. ] A coarse kind of thick woolen cloth, worn by the poor in the Middle Ages; also, a woolen cap or hood worn over the shoulders or over the head. [ 1913 Webster ]

v. i. [ imp. & p. p. Birred p. pr. & vb. n. Birring. ] [ Cf. OE. bur, bir, wind, storm wind, fr. Icel. byrr wind. Perh. imitative. ] To make, or move with, a whirring noise, as of wheels in motion. [ 1913 Webster ]