English: crown glass
Welsh: gwydr pur
Subject: Ystadau a Cadw
English definition: Glass formed by the now obsolete method of spinning molten glass into a disc on the end of a blowpipe; the disc was cooled and then cut into rectangular panes.
Welsh definition: Gwydr a ffurfiwyd drwy’r dull hynafol o droi gwydr tawdd ar plaen pibell nes ei fod yn ddisg; yna oerwyd y disg a’i dorri’n paenau petryal.
Welsh context: Ffynhonnell: Taflen wybodaeth gyhoeddus Cyngor Gwynedd.