Abu Hafs Amr bin Ali said: Abu Bakr (may Allah be pleased with him) had a lean face, and he was called Atiq precisely because of the fineness of his face, and his name was Abdullah bin Uthman. It is also narrated that the Messenger of Allah (peace and blessings be upon him) gave him the name "Atiq" in the sense of being freed from the Fire.
Hadith Referenceالمعجم الكبير للطبراني / العشرة / 5