Union Jack
noun
1
- the national flag of the United Kingdom, consisting of red and white crosses on a blue background and formed by combining the flags of St George, St Andrew, and St Patrick联合王国国旗。亦称UNION FLAG.
- ORIGIN: originally a small British union flag flown as the jack of a ship
2
union jack
(in the US) a small flag consisting of the union from the national flag, flown at the bows of vessels in harbour（美国）船首旗（由国旗象征统一部分组成）。