Ychwanegol, a. augmentative
Ychwanegu, v. to augment
Ychwarddu, v. to cause laughter
Ychwerig, a. playful
Ychydig, n. a little, a few: a. little: adv. little
Ychydigyn, n. a very little
Yd, n. what is; being; corn: adv. it; that; doth; that it
Ydbys, n. vetches, chit-peas
Yden, n. a grain of corn
Ydfaes, n. a corn-field