What does colorfast mean?
Colorfast describes dyed or colored materials whose color resists fading, running, or bleeding when exposed to washing, light, sweat, chlorine, or friction. The term applies chiefly to textiles — clothing, upholstery, yarn, and curtains — though it can describe any dyed surface. A colorfast red sock can share a washing machine with white sheets without turning them pink, which makes the word a staple of care labels, product descriptions, and laundering advice. The word pairs an old sense of 'fast' meaning firmly fixed with 'color', so a colorfast fabric is one whose dye is securely bound to its fibers. Its opposite condition is variously called running, bleeding, or, in dye chemistry, being fugitive. Because colorfastness matters both practically and commercially — it signals durability and quality — the adjective appears constantly in advertising and consumer guidance, and testing for it is a formal part of textile manufacturing standards.
adjectiveOf dyed or colored material, especially fabric: having color that does not fade, run, or bleed when exposed to washing, light, or other conditions.
- (of dyed or printed fabric, yarn, or other material) retaining its color; not fading, running, or bleeding during washing, exposure to light, rubbing, or other treatment
"The towels are guaranteed colorfast, so you can wash them with whites without worry."
"Look for colorfast labels on swimwear, since chlorine and sunlight are hard on dyes."
"She pre-washed the quilt squares to make sure any dye that wasn't fully colorfast came out before sewing."
'Fast' originally meant 'firmly fixed' — so a colorfast shirt is one whose color is literally held fast to the cloth.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of colorfast
Colorfast combines 'color', ultimately from Latin color, with 'fast', an Old English word (fæst) meaning firm, fixed, or secure. That older sense of fast survives in words like steadfast and in phrases such as 'holding fast', even though 'fast' more commonly means quick today. Compound adjectives of the form X-fast arose in English to describe things that hold firm against a given agent — lightfast, waterproof-fast, and colorfast among them. Colorfast became widespread in the nineteenth and twentieth centuries alongside commercial textile dyeing and standardized laundering, when consumers needed assurance that new synthetic dyes would not bleed.
How colorfast is actually used
A technical and commercial term most often encountered on textile care labels and in discussions of laundry, dyeing, and fabric manufacturing. In everyday speech it carries a reassuring, quality-focused connotation — calling something colorfast implies it will survive washing without ruining itself or other garments in the load. The British spelling is colourfast.
Easily confused with colorfast
Waterproof describes resistance to water penetrating a material, while colorfast describes resistance to color fading or bleeding — a fabric can be one without the other.