What does antra mean?
Antra is the plural form of antrum, a term borrowed from Greek that denotes natural cavities or chambers within the body. In modern medicine it most often refers to the paired maxillary sinuses — air-filled spaces in the cheekbones — but it also describes the widened distal region of the stomach near the pylorus. The word appears almost exclusively in clinical settings: radiology reports describing opacified antra, surgical notes, and anatomy textbooks. Its Greek root, antron, originally meant 'cave', a fitting image for these hollow spaces within bone and soft tissue. Writers should remember that antra is plural, so it pairs with plural verbs, while the singular antrum takes singular agreement. For general readers, encountering antra usually signals a discussion of sinus health, dental imaging, or gastric anatomy rather than everyday conversation.
nounAntra is the plural of 'antrum', denoting multiple natural cavities or chambers within the body — such as those found in bone (the maxillary sinuses) or the lower portion of the stomach.
- Plural of antrum: natural cavities or chambers in the body, especially the maxillary sinuses of the skull or the distal portion of the stomach.
"The CT scan revealed fluid accumulation in both maxillary antra."
"Chronic sinusitis had thickened the mucosal lining of both antra."
"Gastric endoscopy showed narrowing at the pyloric antra region."
Antra is itself the plural of antrum and should not be given an additional plural ending.
"Both antra appeared normal on the scan."
Hidden inside your skull right now are air-filled chambers called antra — the same word ancient Greeks used for caves.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of antra
Antra derives from the Greek antron, meaning 'cave' or 'grotto'. The term entered medical Latin as antrum before passing into English anatomical vocabulary, where it was applied to body cavities resembling small caves. The adjective antral and combining form antro- share this same Greek root.
How antra is actually used
Strictly a technical term confined to medical, anatomical, and radiological contexts; it would rarely appear outside clinical literature or exam material. Because it is a plural-only form, it always takes plural verbs ('the antra were clear').
Easily confused with antra
A mantra is a sacred utterance or repeated phrase, whereas antra are anatomical cavities; the words look and sound similar but share no meaning.
Antrum is the singular form referring to one cavity, while antra is its plural referring to two or more.