n. pl. sto·ma·ta (-mə-tə) or sto·mas
1. Botany One of the minute pores in the epidermis of a leaf or stem through which gases and water vapor pass. Also called stomate.
2. Anatomy A small aperture in the surface of a membrane.
3. A surgically constructed opening, especially one in the abdominal wall that permits the passage of waste after a colostomy or ileostomy.
4. Zoology A mouthlike opening, such as the oral cavity of a nematode.
[New Latin, from Greek, mouth.]
stomal, stoma·tal adj.
(click for a larger image)stoma
in a leaf of iceberg lettuce
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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