Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
A repeatable image with dark background and metal grid pattern.
Source V. Hartikainen
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
You guessed it – looks a bit like cloth.
Source Peax Webdesign
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
A background pattern with green vertical stripes. A new striped background pattern. This time a green one.
Source V. Hartikainen
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The image depicts a Japanese Edo pattern called "kanoko or 鹿の子" meaning "fawn" which has a fur with small white spots.
Source Yamachem
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
Seamless pattern inspired by a drawing on Pixabay. To get the tile this is formed from, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin