The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
A pale olive green background with a seamless texture.
Source V. Hartikainen
This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
A seamless pattern formed from a rectangular tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
Prismatic Hypnotic Pattern No Background
Source GDJ
Prismatic Polka Dots Mark II No Background
Source GDJ
Honestly, who does not like a little pipe and mustache?
Source Luca Errico
This one needs to be used in small areas; you can see it repeat.
Source Luca
The base gradient edited so now more details are rendered.
Source Lazur URH
Prismatic Groovy Concentric Background 2
Source GDJ
From an image on opengameart.org shared by rubberduck.
Source Firkin
Prismatic Groovy Concentric Background No Black
Source GDJ