Answer
This is an official answer by QuranicNames.com Staff
Saadaan mean "happy" and it is a Quranic name indirectly mentioned in the Quran as Sa`eed, such as in Surat Hud 11:105: "When that Day comes, not a soul will speak. unless it be by His leave; and of those [that are gathered together], some will be wretched and some, happy."