Meaning: to return in the direction from which you've come, or to make someone do this
- turn back If you get lost, turn back and return the way you came.
- turn sb back The police were turning everybody back because the road had been blocked by a landslide.
- be turned back Anyone who doesn't have a visa will be turned back at the border.
I was on my way to the airport when I realised I had to turn back because