/doh"boy'/ , n.
1. Informal. an American infantryman, esp. in World War I.
2. a rounded mass of dough, boiled or steamed as a dumpling or deep-fried and served as a hot bread.
[ 1675-85; DOUGH + BOY; sense "infantryman," from mid-1860s, is obscurely derived; two plausible, but unsubstantiated claims: doughboy orig. referred to the globular brass buttons on infantry uniforms, likened to the pastry; dough referred to a clay used to clean the white uniform belts ]