What does "dw" literally mean in Welsh?

I am aware that "i" is a preposition. That is enough for my understanding of that word. Prepositions are complicated. But, what is the literal translation or explanation of the word "dw"? There doesn't seem to be one provided here nor by 'Google'. Does anyone have any ideas to help me?

August 10, 2019, 5:59 PM


Learn Welsh in just 5 minutes a day. For free.