disk clutch

from WordNet (r) 3.0 (2006)

disk clutch
    n 1: a friction clutch in which the frictional surfaces are
         disks

from The Collaborative International Dictionary of English v.0.48

Disk clutch \Disk clutch\ (Engin.)
   A friction clutch in which the gripping surfaces are disks or
   more or less resemble disks.
   [Webster 1913 Suppl.]