The word dyngyldai is a nonsense term with no translation.
The song makes good-humored fun of somebody for being a good-for-nothing.

Song Title: Dyngyldai

Riding on a grey horse the color of the sky,
Aren't you the prancing fool?
With your serrated stirrups, you're so annoying,
Clanking them into people, jeez!

Whatever am I going to do with you?
You can't be fixed or spruced up.
If only you were a nice goatskin blanket
Maybe some fixing or sprucing could happen!

Whatever am I going to do with him?
He can't be traded or exchanged.
Now if he were a knife and flint,
There might be some dealing to be done.

Link to CD info