torus

noun

to·​rus ˈtȯr-əs 

plural tori ˈtȯr-ˌī  -ˌē 

1

: a large molding of convex profile commonly occurring as the lowest molding in the base of a column

2

: the thickening of a membrane closing a wood-cell pit (as of gymnosperm tracheids) having the secondary cell wall arched over the pit cavity

3

: a doughnut-shaped surface generated by a circle rotated about an axis in its plane that does not intersect the circle

broadly : toroid

4

: a smooth rounded anatomical protuberance (such as a bony ridge on the skull)

Examples of torus in a Sentence

Recent Examples on the Web

One [Gardner puzzle book] had a picture on the cover of what mathematicians call a torus, the shape of a doughnut or a bagel. —Sarah Lewin Frasier, Scientific American, 29 Oct. 2024

Each chip is connected to six other chips, and the whole system is connected in the shape of a torus to ensure all connecting wires are equally short. —IEEE Spectrum, 8 May 2024

Webb’s instruments were able to tell that most of the droplets of water from the vapor Enceladus regularly spews out don’t stay within the torus near the moon. —Elizabeth Rayne, Ars Technica, 13 June 2023

Billiard trajectories on the table correspond to trajectories on the torus, and vice versa. —Quanta Magazine, 15 Feb. 2024

Word History

Etymology

New Latin, from Latin, protuberance, bulge, torus molding

First Known Use

1563, in the meaning defined at sense 1

Medical Definition

torus

noun

to·​rus ˈtōr-əs, ˈtȯr- 

plural tori ˈtō(ə)r-ˌī  ˈtȯ(ə)r- 

-ˌē

1

: a doughnut-shaped surface generated by a circle rotated about an axis in its plane that does not intersect the circle

2

: a smooth rounded anatomical protuberance (as a bony ridge on the skull)

a supraorbital torus