Updated April 30, 2021.
Anne asked me “Is there a clear distinction between variegated and overdyed threads? I seem to remember from some source that variegated threads are variations/shades of the same color and overdyed are threads that are multicolored. Is that correct?”
What the terms actually mean and how we use them are two different things.
In precise terms “overdyed” threads are threads that are already colored (bleached white is a color in this sense) are dyed. The color of the base thread affects the end color of the thread. So the new color is dyed over the old color.
Let’s say you were dyeing blue. On RTD (ready-to-dye, which are usually a pale cream or natural color) the result would be blue. If you created an overdyed thread over a yellow base, the result would be a greenish-blue. Dyed over red, it would be violet.
In precise terms “variegated” does mean variation in color or shade.
Stitchers use these terms in non-standard ways. We call any thread made by a small manufacturer, no matter the method used to produce it, “overdyes.” These can be colors that are subtle variations in shades of one color, or they can be multi-colored. The picture at the top of the article shows threads stitchers would call overdyed, even though they show very different color schemes.
We use the term “variegated” to refer to those threads, whether shades of one color or not, created by the big manufacturers.
So DMC and Anchor make variegated threads, in our common talk. But Caron threads we call overdyes, even though they may not actually be overdyed.
I like to call those threads that are subtle shades of one color, ‘semi-solid.’ I think it’s more descriptive.