From Wikipedia:

    Hippie (etymology)

Lexicographer Jesse Sheidlower, the principal American editor of the Oxford English Dictionary, argues that the terms hipster and hippie derive from the word hip, whose origins are unknown.[1] The term hipster was coined by Harry Gibson in 1940,[2] in his stage name "Harry the Hipster". Hipster was often used in the 1940s and 1950s to describe jazz performers. The word hippie is also jazz slang from the 1940s, and one of the first recorded usages of the word hippie was in a radio show on November 13, 1945, in which Stan Kenton called Harry Gibson, "Hippie".[3][4] However, Kenton's use of the word was playing off Gibson's nickname "Harry the Hipster." Reminiscing about late 1940s Harlem in his 1964 autobiography, Malcolm X referred to the word hippy as a term that African Americans used to describe a specific type of white man who "acted more Negro than Negroes."[5]

Although the word hippie made isolated appearances during the early 1960s, the first clearly contemporary use of the term appeared in print on September 5, 1965, in the article, "A New Haven for Beatniks", by San Francisco journalist Michael Fallon. In that article, Fallon wrote about the Blue Unicorn coffeehouse, using the term hippie to refer to the new generation of beatniks who had moved from North Beach into the Haight-Ashbury district. New York Times editor and usage writer Theodore M. Bernstein said the paper changed the spelling from hippy to hippie to avoid the ambiguous description of clothing as hippy fashions.