Pinko is a slang term coined in 1925 in the United States to describe a person regarded as being sympathetic to communism, though not necessarily a Communist Party member. It has since come to be used, derogatorily, to describe anyone perceived to have leftist or socialist sympathies.
The term has its origins in the notion that pink is a lighter shade of red, a color associated with communism. Thus pink could describe a "lighter form of communism", purportedly promoted by supporters of socialism who were not themselves actual or "card carrying" communists. The term pinko has a pejorative sense, whereas 'pink' in this definition can be used in a purely descriptive sense, such as in the term pink tide.
The word pinko was coined by Time magazine in 1925 as a variant on the noun and adjective pink, which had been used along with parlor pink since the beginning of the 20th century to refer to those of leftish sympathies, usually with an implication of "effeteness". In the 1920s, for example, a Wall Street Journal editorial described supporters of the progressive politician Robert La Follette as “visionaries, ne’er do wells, parlor pinks, reds, hyphenates [Americans with divided allegiance], soft handed agriculturalists and working men who have never seen a shovel.”
Pinko was widely used during the Cold War to label individuals accused of supporting the Soviet Union, including many supporters of ex-vice president Henry Wallace's 1948 U.S. presidential campaign with the Progressive Party. The word was predominantly used in the United States, where opposition to Communism grew strong among the population, especially during the McCarthy era. It was also in common use in South Africa during the apartheid era. In his two presidential campaigns, Alabama governor George Wallace often railed at what he called "the left-wing pinko press" and "pseudo-pinko-intellectuals."