American soldiers in Vietnam communicated using so much slang and shorthand that it almost seems like its own English dialect. Their language, often both flippant and matter-of-fact, sheds light on how they coped with the horrors of war. Here are 15 memorable terms, from ball game to unbloused.

A second lieutenant, the lowest-ranking officer. The uniform insignia for second lieutenants is one gold bar, which looks like a stick of butter. Second lieutenants were also known as brown bars, since the bar on their camouflage uniform was sometimes brown.

The dap, now ubiquitous in Black American culture, originated with Black soldiers in Vietnam. “At a time when the Black Power movement was burgeoning, racial unrest was prominent in American cities, and draft reforms sent tens of thousands of young African Americans into combat, the dap became an important symbol of unity and survival in a racially turbulent atmosphere,” LaMont Hamilton wrote for the Smithsonian’s Folklife Magazine. “Scholars on the Vietnam War and Black Vietnam vets alike note that the dap derived from a pact Black soldiers took in order to convey their commitment to looking after one another.”