yghenawc, s. [64–5], 67. See achenawc.
ygnat, sm. 125, [139]; — kadeirawc, 117. ygneit, pl. [112]; — Hywel Da, [77], 80.
ygnat llys, 2, 4–6, [8, 10], 15–17, 21, 27, [64], 124, 126.
ygneitaeth, s. 17. See pump.
ymadrawd, sm. 125.
ymardelw, v. 43.
ymaruoll, s. 2.
ymatteb, v. 125.
ymborth, s. 25, 32.
ymborth, v. 31; ymborthet, 28.
ymchoelo, v. 49, 58.
[ymdaeru, v. 64].
ymdangossont, v. 120.
ymdeith, adv. 42, [61].
ymdeith, v. 70, [95, 115–16; ymda, 97].
ymdiredir, v. 32; [ymdiret, 140].
ymdiueicha, v. 82.
ymdwyn, v. 39–40.
ymgoffau, v. [115], 117, [141].
[ymhoeles, v. 60] ; ymhoelir, 124.
ymlad, s. 22, [136]; — kyfadef, 123.
ymlad, v. 85 ; ymladant, 58, [60]; ymladont, 58, [60].
ymlycceir, v. 47.
ymlynet, v. 36.
ymrein, v. [96], 132, [133; ymreher, 98].
[ymrotho, v. 61, 97].
ymyrru, v. 143].
ynuyt, 39, [139].
[yr (= er), 101].
[yscar, v. 94; ysgarho, 141].
ysceuein, s. 72; ysceueint, 69, [74].
yscei, s. 26.
yscol, s. 88.
yscolheic, s. 1, 88, 128; [yscoelheic, 59], yscolheick, 58; yscolheigon, pl. — vrdolyon, 121; [— y llys, 9].
yscolheictawc, s. 58, [59].
yscrybyl, s. 28, 35, [75], 85, 118; — aghynefin, 84; [— trefgord, 74; ysgrybyl, 102].
yscub, sf. 30, 83.
yscubawr, s. 46, 57, [59], 84, [99; ysgubawr, 102. yscuboryeu, pl. 136]. See brenhin; esgubawr.
yscwyd, s. 56.
yskyfarn, s. 22–3, 43, 89.
yscyuarnawc, sf. [77], 80.
yscymundawc, 120.
[ysgall, s. 116].
yspardwneu, pl. 21.
yspeil, s. [111], 120.
yspeilaw, v. 127; [yspeiler, 137]; yspeilet, 87.
yspeit, s. 33; — mach, 85.
[Yspryt Glan, 142],
[yssu, v. 113; yssan, 77]; ysser, [78], 80; ysset, 29; ysso, 82, [97; yssont, 76], See hyys.
ystabyl, s. 57, [59]. ystableu, pl. 21.
ystauell, s. 5, [7], 22, 26–7, 34, 56-7, [59]. See brenhin; dryssawr; gwas; morwyn.
[ystauellawc, a. 100].
ystalwyn, sm. [78], 80, 130, [140].
[ystwc, s. — helyc, 107].
[Ystwyll, s. 110],
[ystyffyleu, pl. 101].
[ystyllawc, 107].
yt, sm. 28, 30, 82–4, [94, 98], 117–18, [139, 143].
ytlan, s. 84.
[yw, s. 107].
[ywen, s. — coet, — sant, 104].