The origin of the town name is no longer known.

The origin of the name is not known for certain.

Most people don't know their origin or take the time to think about it.

His origins and early life were known only to himself.

His parents asked not to spend money until it know its origin.

The origins or meaning of the name are not known.

The origin of the dead bodies is also not known.

The origin of the town's name is not fully known.

The origin and date of first use are not known.

The origins of the name Washington are not fully known.