why was he called by that term that you mentioned above within inverted commas?
He was promoted to the position of "Munshi" by the queen.
Abdul Karim (the Munshi)
After he complained to the Queen that he had been a clerk in India and thus menial work as a waiter was beneath him, he was promoted to the position of "Munshi" in August 1888. 
what is the true story of victoria and abdul Mohammed Abdul Karim known as "the Munshi", was an Indian attendant of Queen Victoria. He served her during the final fourteen years of her reign, gaining her maternal affection over that time. The close platonic relationship between Karim and the Queen led to friction within the Royal Household, the other members of which felt themselves to be superior to him. what did he use to do in his initial life? Karim worked as a "vakil" ("agent" or "representative") for the Nawab of Jaora in the Agency of Agar. when did he start to serve the queen? 23 June 1887
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Abdul Karim (the Munshi) [SEP] Royal servant
In her journal, the Queen writes that she made this change so that he would stay: "I particularly wish to retain his services as he helps me in studying Hindustani, which interests me very much, & he is very intelligent & useful." Photographs of him waiting at table were destroyed and he became the first Indian personal clerk to the Queen. Buksh remained in the Queen's service, but only as a "khidmatgar" or table servant, until his death at Windsor in 1899.