The king of the Tylwyth Teg was called gwydion ab Don, Gwyd referring to a temperament in man's nature.
"The Fairy-Faith in Celtic Countries"
W. Y. Evans Wentz
gwydion wants a wife for his pupil: "Well," says Math, "we will seek, I and thou, by charms and illusions, to form a wife for him out of flowers.
"Selections from the Prose Works of Matthew Arnold"
Matthew Arnold