Moire is a kind of silk, or silk-like cloth, with a wavy pattern that looks like water moving across it. The ripples are pressed into the fabric, so the shine changes as you turn it. Evening dresses and old furniture covers used to love this look. People also stretch the word — often written moiré, with a little mark over the e — for a similar wave that is not cloth at all. When two grids sit on top of each other, a photo of a screen, a fence in front of stripes, you get bands and ripples that were not in the real thing. Printers and photographers usually do not want that. Though actually, fashion is talking about cloth; cameras and printers are talking about a problem. Same shape on the page, two lives. The French word came from English mohair, then English borrowed it back — so this “French” cloth word is, in a roundabout way, an English word coming home.

雲紋綢、波紋綢（布上的水波光澤）。照片或螢幕上不該出現的干涉波紋，台灣常叫「莫爾紋」。