ruby

1 of 2

noun

ru·​by ˈrü-bē 

plural rubies

1

a

: a precious stone that is a red corundum

b

: something (such as a watch bearing) made of ruby

2

a

: the dark red color of the ruby

b

: something resembling a ruby in color

ruby

2 of 2

adjective

: of the color ruby

Examples of ruby in a Sentence

Recent Examples on the Web

Noun

Travelers head to the National Mall to find marble memorials, Smithsonian museums (housing everything from spacecraft to Dorothy’s ruby slippers), and global gatherings (like WorldPride 2025, taking place May 17 to June 8). —Amy Alipio, AFAR Media, 29 Apr. 2025

The plant that inspired such devotion is a beautiful if delicate shrub, with small white flowers and fruits the size and color of rubies. —Wade Davis, Rolling Stone, 6 Apr. 2025

Adjective

The company’s new Aura glasses ($385) change from cool blue to purple, ruby, and even crystal clear with the tap of a finger. —Jennifer Jolly, USA TODAY, 13 Jan. 2025

Trump won Missouri by 18.5 percentage points and 15.4 percentage points in 2016 and 2020, respectively, solidifying the state’s transformation from perennial bellwether to ruby-red bastion with a grassroots Republican base that is very supportive of the 45th president. —David M. Drucker, Washington Examiner, 19 Apr. 2021

Word History

Etymology

Noun

Middle English, from Anglo-French rubi, rubin, from Medieval Latin rubinus, from Latin rubeus reddish; akin to Latin ruber red — more at red

First Known Use

Noun

14th century, in the meaning defined at sense 1a

Adjective

15th century, in the meaning defined above

Phrases Containing ruby

• ruby glass
• ruby spinel
• ruby-throated hummingbird

Rhymes for ruby

• booby

Kids Definition

ruby

1 of 2 noun

ru·​by ˈrü-bē 

plural rubies

1

: a precious stone of a deep red color

2

: the dark red color of the ruby

ruby

2 of 2 adjective

: dark red in color