A deep, slightly bluish red.
"The autumn leaves turned a rich crimson as the sun began to set behind the mountains."
In plain English: Crimson is not really a noun because it describes a deep red color rather than being an object itself.
"The deep crimson color of her dress caught everyone's eye immediately."
Usage: Use the noun form of crimson only when referring specifically to that particular shade of deep, slightly bluish red rather than using it as an adjective for any dark red object. Avoid confusing this specific color name with general terms like "red" or "scarlet," which lack its distinct blue undertone.
To become crimson or deep red; to blush.
"Her cheeks turned crimson when she realized everyone was staring at her mistake."
In plain English: To make something turn bright red, usually by dyeing it.
"The blood crimsoned her white shirt instantly when she cut her finger on broken glass."
of a color at the end of the color spectrum (next to orange); resembling the color of blood or cherries or tomatoes or rubies
"The crimson sunset painted the sky in shades that resembled fresh blood and ripe cherries."
Having a deep red colour.
"The autumn leaves turned a brilliant crimson as the temperature dropped below freezing."
The word crimson comes from the Arabic qirmiz, which originally referred to a red dye made from insects. This term traveled through Old Spanish and French before entering Middle English in the late 14th century.