This car cannot be driven on public roads.
When riding a bicycle on public roads, you must obey traffic rules.
righteousness; justice; right path
Abstract moral sense; often used in philosophical or ethical discussions.
He always strives to follow the path of righteousness.
He was a man who upheld righteousness throughout his life.
You need to be careful when pulling out from a private road onto a public one.
Speeding on public roads is dangerous.
正義 is the common, everyday word for justice, while 公道 is a more formal, literary term for the righteous path.
街道 refers to a historic or major traffic route, whereas 公道 is the legal term for a road open to public use.
正道 and 公道 both mean the 'right path' in an ethical sense, but 正道 is slightly more common in modern moral discourse.
Compound of 公 (public) and 道 (road, way). The abstract sense extends the idea of a 'public way' to a 'righteous path'.