Union Jack

a national ensign of the United Kingdom of Great Britain and Ireland. The national flag of England is the red cross of St. George on a white ground; that of Scotland is the white diagonal cross of St. Andrew on a blue ground; that of Ireland is the red diagonal cross of St. Patrick on a white ground. The three crosses put together form the Union Jack. The triangular portions of the background are blue. The bars representing the crosses are partly red and partly white. Its colors, therefore, are red, white, and blue. Although the American flag was adopted before the Union Jack took its present form, its colors also are derived, as is fitting, from the three flags of the United Kingdom. See Flag