tystysgrif

== Welsh == === Etymology === From tyst (“witness”) +‎ ysgrif (“essay”). === Noun === tystysgrif f (plural tystysgrifau) certificate, diploma ==== Derived terms ==== Tystysgrif Gyffredinol Addysg Uwchradd (“General Certificate of Secondary Education”) === Mutation === === Further reading === R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke, et al., editors (1950–present), “tystysgrif”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies