Definition - What does Stomata mean?
Stomata is the plural word for stoma. These are the pores of a leaf, sometimes called the "mouth," which facilitates the exchange of gases (carbon dioxide and oxygen).
The term includes all the anatomical parts that make up the stomatal complex, which is necessary for the respiration of a plant and also used in photosynthesis.
WineFrog explains Stomata
The stomata allow for the grapevine (or any other plant) to breathe. On some plants, the stomata are located on both the upper side and lower side of the leaves, but on the grapevine, they are found only on the underside of the leaf.
These little pores make up part of the epidermal layer. Carbon dioxide enter the leaves via the stomata that is used for manufacturing carbohydrates during photosynthesis. It is also the anatomy which allows water to exit the leaf, helping it to cool off.