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

Four tanzanites ranging in size from 8 to 12 carats adorn the set’s earrings, bracelet, and necklace, each of which is crafted from an elevated mix of platinum, 18-karat yellow gold, rubies, and diamonds. —Paige Reddinger, Robb Report, 15 Oct. 2025

In a language of diamonds, emeralds, sapphires and rubies, Cartier and Van Cleef & Arpels envisaged elaborate, futuristic pieces that contributed greatly to what is known as Roaring ’20s style. —Sofia Celeste, Footwear News, 11 Oct. 2025

Adjective

The Institute of Agriculture notes that there are a few hummingbirds that surface between November and late March in Tennessee and other Southern states, but these birds are not typically ruby-throat hummingbirds. —Jordan Green, Nashville Tennessean, 21 Aug. 2025

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

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