The Collaborative International Dictionary of English v.0.48:

Turbinal \Tur"bi*nal\, a. [L. turbo, turben, -inis, a top,
   whirl.] (Anat.)
   Rolled in a spiral; scroll-like; turbinate; -- applied to the
   thin, plicated, bony or cartilaginous plates which support
   the olfactory and mucous membranes of the nasal chambers.
   [1913 Webster]

   Note: There are usually several of these plates in each nasal
         chamber. The upper ones, connected directly with the
         ethmoid bone, are called ethmoturbinals, and the
         lower, connected with the maxillae,
         maxillo-turbinals. Incurved portions of the wall of
         the nasal chamber are sometimes called
         pseudoturbinals, to distinguish them from the true
         turbinals which are free outgrowths into the chambers.
         [1913 Webster]