Jump To:

• ruby
  ruby

  noun

  a red variety of corundum, used as a gem.
• Ruby
  Ruby

  noun

  a female given name.

ruby

¹ American  

[roo-bee] / ˈru bi /

noun

• rubies
  plural

1. a red variety of corundum, used as a gem.

2. something made of this stone or one of its imitations, as a bearing in a watch.

3. a deep-red port wine.

4. deep red; carmine.

5. Digital Technology. Ruby, an open-source, high-level programming language that is purely object-oriented.

6. British Printing. a 5½-point type, nearly corresponding in size to American agate.

---

adjective

1. ruby-colored.

   ruby lips.

2. containing or set or adorned with a ruby or rubies.

   a ruby necklace.

Ruby ² American  

[roo-bee] / ˈru bi /

noun

1. a female given name.

---

ruby British  

/ ˈruːbɪ /

noun

1. a deep red transparent precious variety of corundum: occurs naturally in Myanmar and Sri Lanka but is also synthesized. It is used as a gemstone, in lasers, and for bearings and rollers in watchmaking. Formula: Al 2 O 3

2. 1. the deep-red colour of a ruby

   2. ( as adjective )

      ruby lips

3. 1. something resembling, made of, or containing a ruby

   2. ( as modifier )

      ruby necklace

4. (modifier) denoting a fortieth anniversary

   our ruby wedding

5. (formerly) a size of printer's type approximately equal to 5 1/ 2 point

---

ruby Scientific  

/ ro̅o̅′bē /

1. A deep-red, translucent variety of the mineral corundum, containing small amounts of chromium and valued as a gem.

2. Compare sapphire

---

Usage

What does ruby mean? A ruby is a transparent red gemstone. Rubies are one of the most well-known gemstones, along with diamonds, emeralds, and sapphires. They are classified as precious gems, meaning that they have a high commercial value. Rubies are quite rare and are considered one of the most valuable gems. Besides diamond, ruby is one of the hardest known natural substances. The ruby is the traditional birthstone for the month of July. It is associated with the zodiac signs Capricorn and Leo. The word ruby is also used to refer to a jewel-toned red color or describe things that are that color. The word is often used in the term ruby red, as in Look at that ruby red sports car! The word ruby is sometimes used to describe a 40-year anniversary, as in It’s my parents’ ruby anniversary this year—I can’t believe they’ve been married for 40 years!Ruby is also a given name, traditionally a female one. It’s also the name of a programming language. Example: The ring features a large ruby surrounded by diamonds. 

Other Word Forms

Derived Forms

• ruby-like
  adjective
• rubylike
  adjective

Inflected Forms

Nouns

• rubies
  plural

Etymology

Origin of ruby

First recorded in 1300–50; Middle English noun rubi from Old French, from Old Provençal robi(n) , from Medieval Latin rubīnus (lapis) “red (stone),” derivative of Latin ruber, rubeus red ¹

Explanation

A ruby is a gemstone that's usually a deep red. You can also describe things that are this same red color as ruby, like Dorothy's ruby slippers. Rubies are one of four types of precious stones — the others are diamonds, emeralds, and sapphires. A ruby can be any reddish shade from pink to dark red, and it's the official birthstone for people born in July. Less expensive rubies are often treated with high heat, which improves the color and clarity of the stone. Ruby comes from the Medieval Latin rubinus lapis, "red stone."

Example Sentences

See Examples For:

ruby Ruby rubies

At its center is a compact red source that closely resembles a little red dot and even evokes the ruby red fruit of the desert cactus.

From Science Daily ● Aug. 17, 2026

German counter with mustard-slicked potatoes and ruby cabbage slaw?

From Salon ● Feb. 12, 2026

Embrace those same fuzzy feelings, but in a grown-up style, with Burberry’s shearling scarf in a deep ruby red perfect for fall.

From Los Angeles Times ● Oct. 20, 2025

“It’s ruby red with four golden stamens,” her mother replies.

From The Wall Street Journal ● Oct. 9, 2025

The glass cases contained dozens of keepsakes: a ruby the size of a man’s fist, a wedge of gold shaped like a sandwich, even the Thunder Gong she’d read about in the book.

From "The Reader" by Traci Chee

“It was a major attack in terms of what we see in volume,” said Marty Haught, director of open source at Ruby Central, the nonprofit company that operates RubyGems.

From The Wall Street Journal ● Sep. 11, 2026

“It’s incredible for Ruby to be clicking this fast at a new position. As for Brooklyn, she’s so gifted at reading the quarterback. She had two pick-sixes at the Ventura Showcase.”

From Los Angeles Times ● Sep. 8, 2026

There, an ailing playwright named M lives with his wife, S—who is an actress—and their precocious daughter, Ruby.

From The Wall Street Journal ● Sep. 1, 2026

Why did Ruby have to go so many years without the support she needed?

From Los Angeles Times ● Aug. 26, 2026

“We can do them when Ruby gets here.”

From "How to Disappear Completely" by Ali Standish

A stunning jeweled dagger hilt and scabbard from Jahangir’s reign incorporate more than 2,000 diamonds, rubies and emeralds set in an intricate pattern in gold.

From The Wall Street Journal ● Jul. 11, 2026

Bars and rings trade at a premium to the world price at gold and jewellery shops across the country, where bullion emblazoned with dragons is sold alongside ornate goldware inlaid with pearls and rubies.

From Barron's ● Jan. 30, 2026

He says we will see brightly coloured gemstones like rubies, emeralds, and sapphires take the spotlight and "a lot of asymmetrical designs and chunky, unconventional shapes".

From BBC ● Sep. 11, 2024

It contains just under 400 diamonds, rubies and sapphires and is set onto yellow gold, with a total karat weight of approximately 6 carats.

From Los Angeles Times ● May 8, 2024

They were red eyre, homicidal, terrific, seeming actually to give out light They were like rubies filled with flame.

From "The Once and Future King" by T. H. White

Related Words

• cardinal
• coral
• crimson
• flaming
• glowing
• maroon
• rose
• wine