Ddafydd, Moelyci; but mynydd ‘mountain’ and bryn ‘hill’ are m., and so therefore are names formed from them, as Mỿnỿ́ddmawr.
(5) iaith ‘language’, and names of languages: y Gymraeg wen E.P. 217; but when the name denotes matter written in a language it is m.: y Cymraeg hwn ‘this (piece of) Welsh’. llythyren ‘letter’ is fem., and names of letters and sounds: a fain ‘thin a’ (i.e. ‘æ’).
(6) Names of trees: derwen ‘oak’, dâr ‘oak’, collen ‘hazel’, etc.
(7) Collective nouns denoting communities, etc.: y genedl ‘the nation’, y werin ‘the people, the crew (of a ship)’, y bobl ‘the people’, y bendefigaeth ‘the nobility’, y gymanfa ‘the assembly’, y gynulleidfa ‘the congregation’, y glêr ‘the bards’ (y fân glêr L.G.C. 71), y dorf, y dyrfa ‘the crowd’, y gynhadledd ‘the assembly’; with some late exceptions, as y cyngor ‘the council’, y bwrdd ‘the board’.
§ 139. The gender of a derivative noun is determined by its ending.
i. The following endings form m. nouns: ‑ach dim. sg., ‑aint, ‑awd, ‑cyn, ‑dab ‑deb, ‑der, ‑did, ‑dod, ‑dra, ‑dwr, ‑edd, ‑hâd, ‑i ‑ni ‑i̯oni, ‑i̯ad ‑ad, ‑i̯ant, ‑inab ‑ineb, ‑rwydd, ‑wch (‑wg), ‑yd, ‑yn.
Examples: bwbach, henaint, traethawd, llecyn, un-dab, ‑deb, blinder, gwendid, cryndod, ffieidd-dra, cryfdwr, amynedd, glanhâd, tlodi, noethni, drygioni, cariad, teimlad, mwyni̯ant, doethin-ab, ‑eb, enbydrwydd, tywyll-wch, (‑wg), iechyd, offeryn.
Exceptions: awdurdod, trindod; buchedd, cynghanedd, trugaredd, see § 143 iii (13); cenadwri (f. after cennad); adeilad § 205; caniad ‘song’ (f. after cân) but caniad ‘singing’ m.; galwad (f. after galwedigaeth); blwyddyn, elltrewyn, odyn, telyn, twymyn. In the last group ‑yn is not the sg. ending ‑ynn, see § 126 iv.
ii. The following endings form f. nouns: ‑ach (abstract), ‑aeth ‑i̯aeth etc., ‑as, ‑ed, ‑ell, ‑en, ‑es, ‑fa, ‑ur.
Examples: cyfeillach, cosbedigaeth, athrawiaeth, teyrnas, colled, asgell, seren, llynges, porfa, natur, pladur.
There are many exceptions in ‑aeth and ‑i̯aeth; as claddedigaeth, darfodedigaeth, gwasanaeth, hiraeth, amrywi̯aeth, gwahaniaeth, lluniaeth.—Other exceptions are lludded, caethiwed, syched, pared; castell, cawell, hiriell ‘angel’ D. 43; maharen; hanes m. in N.W.—gw̯nïadur ‘thimble’ is m. in N.W.; names of persons in ‑ur are mas. (f. ‑ures).
iii. The following endings form derivatives having the same gender as the noun to which they are affixed: ‑aid ‘‑ful’, ‑an dimin., ‑awd, ‑od ‘stroke, blow’; as crochanaid m. ‘potful’; llwyaid f. ‘spoonful; maban m. ‘babe’, gwreigan f. ‘little woman’, dynan com. ‘little person’; cleddyfod m. ‘stroke of sword’, ffonnod f. ‘blow of a stick’, dyrnod m., arfod f. (cleddyfawd f. D.G. 473 is exceptional).
iv. ‑og (‑awc) forms m. titles and designations, as tywysog ‘prince’, marchog ‘knight’, swyddog ‘officer’, cymydog ‘neighbour’, taeog ‘villain’; and f. terms of reproach, as ffolog ‘fool’ f., budrog ‘slattern’, slebog id. Names of inanimate objects in ‑og are generally f., as arffedog ‘apron’, clustog ‘cushion’, mawnog ‘bog’.
