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 unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
A comeback for you: the popular Escheresque, now in black.
Source Patten
Number 5 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
This is the remix of "polka dot seamless pattern".The image depicts polka dot seamless pattern.
Source Yamachem
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
From a drawing in 'Prose and Verse ', William Linton, 1836.
Source Firkin
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A new one called white wall, not by me this time.
Source Yuji Honzawa
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Prismatic Chevrons Pattern 5 With Background
Source GDJ
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
That’s what it is, a dark dot. Or sort of carbon looking.
Source Tsvetelin Nikolov
The tile for this is based on a repeating unit close to a design on Pixabay. It can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
It’s a hole, in a pattern. On your website. Dig it!
Source Josh Green
Fix side and a seamless pattern formed from circles.
Source SliverKnight
It looks very nice I think.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo