hippie

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A member of a counterculture originating in the United States in the 1960s, typically characterized by unconventional dress and behavior, communal or transient lifestyles, opposition to war, and liberal attitudes toward sexuality and the use of marijuana and psychedelic drugs.

from the GNU version of the Collaborative International Dictionary of English.

• noun Someone who rejects the established culture, dresses casually, and advocates extreme liberalism in politics and lifestyle. Used especially of those in the late 1960's, mostly in their late teens and early twenties, who conspicuously rejected traditional culture by dressing casually, if male wore their hair long, and wore folksy or used clothing adorned with beads, headbands, and often flowers; they emphasized the importance of love and direct personal relations rather than success-oriented businesslike behavior, strove for spontaneity, sometimes lived communally, and in some cases tried to expand their consciousness by various psychological techniques such as meditation, or through the use of consciousness-altering drugs such as marijuana or LSD. By the end of the Vietnam war in the 1970's, the numbers of people living a visibly hippie lifestyle had dramatically decreased, though some people continue to develop similar views and live with the same outlook.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun in the 1950s A teenager who imitated the beatniks
• noun in the 1960s; still widely used in reference to that era One who chooses not to conform to prevailing social norms: especially one who ascribes to values or actions such as acceptance or self-practice of recreational drug use, liberal or radical sexual mores, advocacy of communal living, strong pacifism or anti-war sentiment, etc.
• noun Someone with unusually long hair.
• noun Someone who dresses in a hippie style.
• noun One who is hip.
• adjective Of or pertaining to hippies: e.g., “the hippie era”.
• adjective colloquial Not conforming to generally accepted standards: e.g., “Despite being for the widely-used Windows operating system, rather than using the commonly-used RAR or ZIP file-compression formats, they used a bunch of hippie compression formats instead”.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun someone who rejects the established culture; advocates extreme liberalism in politics and lifestyle