The Collaborative International Dictionary of English v.0.48:

Levesel \Lev"e*sel\ (l[e^]v"[-e]*s[e^]l), n. [AS. le['a]f a leaf
   + s[ae]l, sel, a room, a hall.]
   A leafy shelter; a place covered with foliage. [Obs.]
   [1913 Webster]

         Behind the mill, under a levesel.        --Chaucer.
   [1913 Webster]