-stome

The combining form –stome is used like a suffix that can indicate an “organism having a mouth or mouthlike organ” or refer to a “mouthlike organ.” It is used in many scientific terms, especially in biology and zoology.

The form -stome comes from the Greek stóma, meaning “mouth.” This root is the source of the English word stoma (a technical term for a mouth, among other senses) and is related to stomach. Stomach? Our stomachs and mouths are certainly connected—and etymologically so, too. Discover the connection at our entry for the word.

Closely related to -stome are -stomous and -stomy. Corresponding forms of -stomous combined to the beginning of words are stomato- and stomat-. Learn more about the specific applications of these forms at our Words That Use articles for them.

One example of a term from biology that features the combining form -stome is monostome, “having a single mouth, pore, or stoma.”

The first part of the word, mono-, means “single” or “one.” The rest of the word, -stome, denotes an “organism having a mouthlike organ.” Monostome, then, literally translates to “single-mouthed organism.”

What are some words that use the combining form -stome?

• cytostome
• gnathostome
• hypostome
• plagiostome
• pneumostome
• peristome

What are some other forms that -stome may be commonly confused with?

• -soma
• -some
• -tome
• -tomous
• -tomy

The combining form pneumo- means “breath” or “lung.” Gastropods, like snails and slugs, have a pnemuostome. Based on the meaning pneumo- and -stome, what is pneumostome for such creatures?