dyddiadur

== Welsh == === Etymology === From dydd (“day”) +‎ -iadur. === Noun === dyddiadur m (plural dyddiaduron) diary, journal calendar, almanac === Mutation === === References === R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke, et al., editors (1950–present), “dyddiadur”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies