Complete the idiom for an achievement: "a feather in your ___."

An abundance of flowers is said to have given which state its name when the Spanish arrived in 1513? What term for an accomplished young man is also a nickname for Batman's sidekick Robin? In a criminal trial, the accused person together with his or her lawyers is known as what? In golf, an "ace" is another term for which feat? Which word means both an acrobat and a flat-bottomed drinking glass? An act of the early 1900s united the Cape Colony, Natal, Transvaal and Orange River Colony to form which country? A 1986 act named the chairman of which panel as the president's principal military adviser? An act of March 3, 1863, established what, which became the subject of riots in New York that July?