torus
|to-rus|
🇺🇸
/ˈtɔrəs/
🇬🇧
/ˈtɔːrəs/
ring-shaped bulge
Etymology
'torus' originates from Latin, specifically the word 'torus', where it meant 'cushion, swelling, bulge'.
'torus' in Latin was adopted into Medieval and Scientific Latin with senses for a rounded molding and bulge; it then entered English in the specialized senses (architecture, anatomy, mathematics) as 'torus'.
Initially, it meant 'cushion' or 'swelling' in Latin, and over time this physical sense developed into architectural and anatomical senses of a rounded bulge and later into the geometric/mathematical sense of a ring-shaped surface.
Meanings by Part of Speech
Noun 1
a doughnut-shaped surface or solid in mathematics; specifically, the surface of revolution generated by revolving a circle in three-dimensional space about an axis coplanar with the circle that does not intersect it (a genus-1 surface in topology).
In topology, a torus is a surface of genus one that can be visualized as a doughnut.
Synonyms
Noun 2
an architectural molding that is a large convex, semicircular profile, typically found at the base of a column.
The base of the classical column featured a prominent torus molding.
Synonyms
Noun 3
a localized bony protuberance found in anatomy, such as the torus palatinus (on the palate) or torus mandibularis (on the mandible).
The dentist noted a small torus on the patient's palate during the examination.
Synonyms
Last updated: 2025/12/13 20:49