The black triangle was a badge used in Nazi concentration camps to mark prisoners as "asocial" or "arbeitsscheu" (work-shy). It was later adopted as a lesbian or feminist symbol of pride and , on the assumption that the Nazis included lesbians in the "asocial" category. More recently it has been adopted by UK disabled people's organisations responding to increasing press allegations that disabled benefit recipients are workshy.
The symbol originates from Nazi concentration camps, where every prisoner had to wear one of the Nazi concentration camp badges on their jacket, the color of which categorized them according to the reason for their internment. Individuals deemed "asocial" had to wear the black triangle. Many black triangle prisoners were either mentally disabled or mentally ill. The homeless were also included, as were alcoholics, the habitually "work-shy", Roma and Sinti, prostitutes, and others (including draft dodgers and pacifists).
Lesbians have over time claimed the black triangle as a symbol of defiance against repression and discrimination, and it is considered a counterpart to the gay pink triangle. Lesbians in Germany and the United States began using the black triangle as a pride symbol in the 1980s.
The use of the symbol as a sign of lesbian victimization has been challenged on the grounds that lesbian sex was not criminal under Paragraph 175 of the Nazi legislation on sexual behavior, and there is no record of the black triangle having been imposed on lesbians, or of lesbians as a group being confined to concentration camps. The archive of the memorial site of Ravensbrück has evidence of four women with an additional remark of being lesbians: two of them had been persecuted for political reasons, two for being Jewish. One of the Jewish inmates was given a black triangle due to sexual contacts with non-Jews.
It is possible that Playing for Time ('Sursis pour l'orchestre'), a holocaust memoir by Fania Fénelon, helped create the belief that the black triangle was worn by lesbians. Fénelon's memoir includes lesbian themes and describes an evening of entertainment in the asocials' barracks as the "Black Triangles' Ball."