allweddol

== Welsh == === Etymology === From allwedd (“key”) +‎ -ol. === Adjective === allweddol (feminine singular allweddol, plural allweddol, equative mor allweddol, comparative mwy allweddol, superlative mwyaf allweddol) key, crucial, critical === Mutation === === Further reading === R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke, et al., editors (1950–present), “allweddol”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies