(4) Most compound adjectives, as hy-glyw, hy-glod, e-ang, ffrwyth-lon, melỿs-lais, etc. But when the second element is an adj. which may take ‑i̯on, the ending is sometimes affixed to the compound; thus claer-wynnẏon Ỻ.A. 92 ‘bright’, gloyw-ẟuon do. 93 ‘glossy-back’; glas-feinion D.G. 87 ‘green and slender’, tal- gryfi̯on Ezek. iii 7 “of an hard forehead”.
D. 56 quotes cyn-dynion, erchyllion (erch-hyllion) as exceptional forms in
- Dynion cyndynion dinerth
- Hyllion erchyllion a cherth.—Anon.
‘Stubborn (but) weak men, ugly, hideous and strange.’
iii. Many adjectives have substantival plurals used partly as abstract nouns as uchelion Gr.O. 120 ‘heights’, but chiefly to denote classes of persons; the sg. is also in some cases substantival. The pl. is formed either by affection or by adding ‑i̯on or ‑i̯aid, Ml. W. ‑ẏon, ‑ẏeit; the latter is used for persons only, and causes the same penult, affection as ‑i̯on, except in late formations. Thus caeth ‘slave’ pl. keith, Mn. W. caith L.G.C. 63, or Ml. W. keithẏeit or Mn. W. caethion; byddar ‘deaf’ pl. byddair, later formation byddariaid; balch ‘proud’ pl. beilch r.p. 1334 l. 46, beilchion, beilchiaid; truan ‘wretch’ pl. truain, trueinion, trueiniaid; gwan ‘weak’, pl. gweinẏon m.a. i 220b, gweinẏeit r.p. 1196, Mn. W. gweiniaid; dall ‘blind’ pl. deillion, deilliaid.
- Ar ol y ferch ar ŵyl Fair
- O gloi’r bedd e glyw’r byddair.—T.A., c. ii 83.
‘The deaf hear [the lamentations] for the maid on Lady Day at the closing of the grave.’
- A’i lun gwrol yn gorwedd
- Ef a wna i’r beilch ofni’r bedd.—T.A., a 14975/107.
‘Since his manly form lies [in it], he makes the proud fear the grave.’
- Be chwilid pob ach aliwn,
- Bylchau’n ach beilchion a wn.—TA., a 14966/277.
‘If every alien pedigree were examined I know gaps in the pedigree of proud ones.’
- A phlaid o feilchiaid a fydd.—D.E., p 100/249.
‘And there will be a company of the proud.’