First geologic attestations of the "subduct" words date to 1970, In ordinary English "to subduct", or "to subduce" (from Latin "subducere", “to lead away”) are transitive verbs requiring a subject to perform an action on an object not itself, here the lower plate, which has then been "subducted" (“removed”). The geological term is "consumed," which happens the geological moment the lower plate slips under, even though it may persist for some time until its remelting and dissipation. In this conceptual model, plate is continually being used up. The identity of the subject, the consumer, or agent of consumption, is left unstated. Some sources accept this subject-object construct.