stoma

/ˈstoʊmə/

Other forms: stomata

In humans, a stoma is any opening or hole in the body. In plants, it's an opening that acts as a sort of mouth, allowing gas exchange.

Stoma is a Greek word that means "mouth," and your mouth is indeed one kind of stoma, or natural opening in your body. Ears and nostrils are also stomas, as are holes created through surgery. An operation to help a patient breathe might create a stoma in their neck, for example. You can only see tiny plant stomas through a microscope; these small openings allow plants to take in the carbon dioxide they need for photosynthesis.

Definitions of stoma

1. noun

   a minute epidermal pore in a leaf or stem through which gases and water vapor can pass
   synonyms: pore, stomate

   types:

   germ pore

   a pore in the outer wall of a spore or pollen grain through which the germ tube or pollen tube makes its exit on germination

   hydathode, water pore, water stoma

   a pore that exudes water on the surface or margin of a leaf of higher plants

   lenticel

   one of many raised pores on the stems of woody plants that allow the interchange of gas between the atmosphere and the interior tissue

   type of:

   aperture

   a natural opening in something
2. noun

   a mouth or mouthlike opening (especially one created by surgery on the surface of the body to create an opening to an internal organ)
   type of:

   opening, orifice, porta

   an aperture or hole that opens into a bodily cavity