Who is considered as infidel (kafir) from the viewpoint of noble Qur'an?

The word Kafir (infidel) is used many times in noble Qur'an. [\[Ref\]][1] such as: > يُرِيدُونَ أَن يُطْفِئُوا نُورَ اللَّـهِ بِأَفْوَاهِهِمْ وَيَأْبَى > اللَّـهُ إِلَّا أَن يُتِمَّ نُورَهُ وَلَوْ كَرِهَ الْكَافِرُونَ > >*Sahih international translation*: > They want to extinguish the light of Allah with their mouths, but > Allah refuses except to perfect His light, although the disbelievers > dislike it. [\[9:32\]][2] Can a comprehensive definition of "infidel" be derived using Qur'anic verses? In other words, Who is infidel (kafir) in the Qur'an point of view?