In Estonian, nupp means button, bud, or knob. It really is a bump, and bumps have been used to glorious effect in Estonian lace knitting. You can see them quite well in this image of Madli’s Shawl from Nancy Bush’s stand-out book Knitted Lace of Estonia (Loveland, Colorado: Interweave, 2008).
In an article Nancy wrote for the July/August 2010 issue of PieceWork, she described how to make a nupp: “[T]he nupp is created, beginning on the right side of the work, by increasing a number of stitches from one. Usually, the increases are made by knitting five or seven stitches into the “mother stitch,” working a yarnover, knitting into the first stitch again, and repeating both the yarnover and the knit stitch again until the desired number has been achieved. On the next row, a wrong-side row, the increased stitches are purled together.”
Nancy explains: “The [Leaf and Nupp Shawl] pattern is a mix of garter stripes embellished with nupps and a double leaf motif and bordered with a very decorative openwork zigzag at the top and bottom.”
Happy knitting,
Jeane