- 十字路口 (shízì lùkǒu) A 4-way intersection (the normal American assumption for such being that the streets meet at 90 degree intervals).
- 丁字路口 (dīngzì lùkǒu) A T-shaped intersection, although in my experience Americans don't necessarily describe them as such, or as a "T intersection" (unlike "4-way intersection", which is common parlance). For directions, it seems more common to say or hear, "Drive down street 1 until it ends, then turn left (or right) on street 2." or possibly "Drive down street 1, which ends in a T. Go left (or right) on street 2."
I've never heard of the character 丫(yā; girl/servant girl) being used to describe forks in the road, even if it seems well suited for such. In truth, the typical fork in the road is more like the shape of a divining rod than the shape of a typical fork. Hmm, I guess sometimes people describe such as a Y-intersection, but fork is more common by far. Of course, the 丫 character, a divining rod, and the capital letter Y are all similar in shape.