Wikipedia
A blue discharge (also known as a "blue ticket") was a form of administrative military discharge formerly issued by the United States beginning in 1916. It was neither honorable nor dishonorable. The blue ticket became the discharge of choice for commanders seeking to remove homosexual service members from the ranks. They were also issued disproportionately to African Americans.
Service members holding a blue discharge were subjected to discrimination in civilian life. They were denied the benefits of the G.I. Bill by the Veterans Administration and had difficulty finding work because employers were aware of the negative connotations of a blue discharge. Following intense criticism in the press—especially the black press, because of the high percentage of African Americans who received blue discharges—and in Congress, the blue discharge was discontinued in 1947, replaced by two new classifications: general and undesirable.
Usage examples of "blue discharge".
He was gazing out of his bedroom window at the cloud patterns when the sky lit with a shimmering blue discharge like an intense aurora.
There was a pop and a tiny burst of blue discharge around the bolt's base.
There was a faint gleaming yellowish-blue discharge, and a slight popping sound, and the policeman tumbled backward as though he had been struck by an electric bolt.