-adur

From Proto-Brythonic *-adʉr.

-adur m (plural -adurioù)

1. To make a noun of another word. The meaning of the noun can vary.

   ‎deiz (“day”) + ‎-adur → ‎deiziadur (“calendar”)

   ‎ger (“word”) + ‎-adur → ‎geriadur (“dictionary”)

   ‎yezh (“language”) + ‎-adur → ‎yezhadur (“grammar”)

• -iadur

From Proto-Brythonic *-adʉr. Cf. Latin -ātor.

• (North Wales) IPA^(key): /ˈadɨ̞r/
• (South Wales) IPA^(key): /ˈa(ː)dɪr/

-adur m (plural -aduron or -aduriaid)

1. agent suffix; usually added to a verbal root

   ‎ffoi (“to flee”) + ‎-adur → ‎ffoadur (“refugee”)

   ‎hen (“old”) + ‎-adur → ‎henadur (“elder, presbyter”)

2. book

   ‎enwi (“to name”) + ‎-adur → ‎enwadur (“glossary”)

   ‎merthyr (“martyr”) + ‎-adur → ‎merthyradur (“martyrology”)

3. instrument

   ‎mwy (“bigger”) + ‎-adur → ‎mwyadur (“microscope”)

   ‎palu (“to dig”) + ‎-adur → ‎pladur (“scythe”)

When referring to a human agent, the plural form of this suffix is -aduriaid. Otherwise, the plural is usually -aduron.

R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke et al., editors (1950–present), “-adur”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies