ˈepəˌstōm noun
also epis·to·ma ə̇ˈpistəmə
( plural ep·i·stomes ˈepəˌstōmz ; also ep·i·sto·ma·ta ˌepəˈstōməd.ə)
Etymology: New Latin epistoma, from epi- + -stoma
1.
a. : the region between the antennae and the mouth of a crustacean
b. : a plate covering this region
2.
a. : the region between the labrum and the epicranium of an insect
b. : clypeus
3. : the region just above the mouth of some two-winged flies
4. : a labiate organ covering the mouth in various bryozoans
5. : an anterior median plate on the doublure of some trilobites