ruby

¹ru·by

noun \ˈrü-bē\

plural rubies

Definition of RUBY

1

a : a precious stone that is a red corundum

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

2

a : the dark red color of the ruby

b : something resembling a ruby in color

Origin of RUBY

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: 14th century

Rhymes with RUBY

booby, looby

²ruby

adjective

Definition of RUBY

: of the color ruby

First Known Use of RUBY

1508

ruby

noun    (Concise Encyclopedia)

Gemstone composed of transparent red corundum. Its colour varies from deep to pale red, in some cases with a tinge of purple, depending on chromium and iron content; the most valued is a pigeon-blood red. When it is cut and polished, ruby is a brilliant (light-deflecting) stone, but it lacks fire (flashes of colour). Ruby is a mineral of very limited distribution. Its best-known source is in Myanmar, and rubies have also been found in Thailand, Sri Lanka, and elsewhere. Rubies have been produced synthetically with much success; those containing 2.5% chromic oxide have the prized pigeon-blood red colour.