Definition of stoma
noun (plural stomas or stomata /-mətə, ˌstōˈmätə/)Botany
- any of the minute pores in the epidermis of the leaf or stem of a plant, forming a slit of variable width that allows movement of gases in and out of the intercellular spaces. Also called stomate.
late 17th century: modern Latin, from Greek stoma 'mouth'