Why is Pakistan callled Pakistan?

The traditional view of Urdu speaking people of Pakistan is that the meaning derived from the urdu word "Pak" (pronounced (Paak in urdu) and the urdu word "stan" (pronounced Staanin urdu). So in traditional thinking the word Pakistan means "Land of the Pure. However the word "PAKISTAN" was first used by Chaudhry Rahmat Ali AKA Rehmat Ali Khan an Indian born British Student who was studying in Cambridge University, UK. On January 28, 1933, he voiced his ideas in the pamphlet entitled "Now or Never; Are We to Live or Perish Forever?". The word 'Pakstan' referred to ONLY "the five Northern units of India, Viz: P unjab, A fghanistan province, K ashmir, S ind and Baluchis tan. Already we can see this definition of the land mass of Pakistan is a contrast to the actual final land mass that became East and West Pakistan. In fact with reference to East Pakistan, He offered "Bang-i-Islam" for a Muslim homeland in Bengal and "Usmanistan" for a Muslim homeland in the Deccan. He also suggested "Dinia" (place of religion) as a name for a subcontinent for various religions. This is relevant because Rehmat Ali became disenchanted with the independence movement. He saw his ideas being used but in a way that had caused mass bloodshed to both sides of the partition. He was also very disappointed about how the land had been divided especially as East and West Pakistan were many 1,000 of miles apart. Rehmats Ali's reward for inventing the name was exile from Pakistan and he now rests in a grave in Cambridge in Newmarket Road Cemetery.