bugeilio â gwialen haearn

== Welsh == === Etymology === Literally, “to shepherd with an iron rod”. === Verb === bugeilio â gwialen haearn (first-person singular present bugeiliaf â gwialen haearn) (idiomatic) to rule with a rod of iron === Further reading === R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke, et al., editors (1950–present), “bugeilio â gwialen haearn”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies