“Hippie” can mean to be hip; and “hippy”, to have hips.
While definitions for “hippy” are generally the same, research on definitions of “hippie” vary somewhat. Per a Microsoft search: hippie — “(especially in the 1960s) a person of unconventional appearance, typically having long hair, associated with a subculture involving a rejection of conventional values and the taking of hallucinogenic drugs”. Per Merriam-Webster: Hippie — “a usually young person who rejects the mores of established society (as by dressing unconventionally or favoring communal living) and advocates a nonviolent ethic; broadly : a long-haired unconventionally dressed young person”. Per dictionary.com — “a person, especially of the late 1960s, who rejected established institutions and values and sought spontaneity, direct personal relations expressing love, and expanded consciousness, often expressed externally in the wearing of casual, folksy clothing and of beads, headbands, used garments, etc.” As a person who identified with that peace-loving, musical, colorful culture but never took drugs, I especially like the last definition. But, admittedly, I am also hippy.