arddegau

== Welsh == === Etymology === From ar (“on”) +‎ deg (“ten”), generalised from tri ar ddeg (“thirteen”), pedwar ar ddeg (“fourteen”), etc. === Noun === arddegau (no singular) teens (numbers from 11 to 19) Synonym: undegau teens, teenage years ==== Coordinate terms ==== ugeiniau, tridegau, pedwardegau, pumdegau, chwedegau, saithdegau, wythdegau, nawdegau ==== Derived terms ==== arddegyn m, arddegen f (“teenager”) yn ei arddegau (“teenaged, in one's teens”) === Mutation === === References === R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke, et al., editors (1950–present), “arddegau”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies