subduct sub·duct (səb-dŭkt')
v. sub·duct·ed, sub·duct·ing, sub·ducts
To pull or draw downward.
A geologic process in which one edge of one lithospheric plate is forced below the edge of another. The denser of the two plates sinks beneath the other. As it descends, the plate often generates seismic and volcanic activity (from melting and upward migration of magma) in the overriding plate. Compare obduction.