Primary
''atrium'' ▫ᴱᴺ|Definition|1st|20260331180822-00-⌔
atrium - Wiktionary, the free dictionary
English
Noun
atrium (plural atria or atriums)
- (architecture) A central room or space in ancient Roman homes, open to the sky in the middle; a similar space in other buildings.
- (architecture) A square hall lit by daylight from above, into which rooms open at one or more levels.
- (anatomy) A cavity, entrance, or passage.
- ✤ an atrium of the infundibula of the lungs
- (biology) Any enclosed body cavity or chamber.
- (anatomy) An upper chamber of the heart that receives blood from the veins and forces it into a ventricle. In higher vertebrates, the right atrium receives blood from the superior vena cava and inferior vena cava, and the left atrium receives blood from the left and right pulmonary veins.
- (anatomy) A microscopic air sac within a pulmonary alveolus.
- (palynology) A cavity inside a porate aperture of a pollen grain formed by the separation of the sexine and nexine layers, widening toward the interior of the grain.
- ✤ Nexine 0.5μ thick, separating from the sexine about 5μ from the pore and forming a deep, well-defined atrium.1
Etymology
From Latin ātrium (“entry hall”), from Etruscan.
Pronunciation
- IPA: /ˈeɪ.tɹi.əm/
- Audio (Southern England): 🔊
- Hyphenation: a‧tri‧um
Printed 2026-06-28.
(echo:: @ ⌗)
Link to original Footnotes
1965, Janet Kircher Warter, Palynology of a Lignite of Lower Eocene (Wilcox) Age from Kemper County , page 52: ↩
Secondary
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