Padparadscha Sapphire is a Sapphire which has “Pinkish Orange” color, it is an ancient name with a meaning of “Lotus Flower”.
The color of this type of a Sapphire is still a big debate, but the one known so far is “pinkish orange”. The biggest market for this sapphire is in Japan. Most of reputed labs are in Japan. Once they check them and approve, it is accepted everywhere.
Many years ago, Padparadscha was grouped as a Ruby. But for ruby to be a ruby it has to be red, or dominated with red color for corundum in order to be considered as a ruby.
Note that both heated and unheated sapphires are termed as Padparadscha.