mastication (n.)

"the action of chewing," early 15c., masticacioun, from Old French masticacion and directly from Latin masticationem (nominative masticatio), noun of action from past-participle stem of masticare "to chew" (source of Old French maschier, French mâcher), which is probably from a Greek source related to mastikhan "to gnash the teeth," from PIE *mendh- "to chew" (see mandible), though Beekes suggests the group may be of Pre-Greek origin.